diff --git a/client/tools/api-docs/bonus.html b/client/tools/api-docs/bonus.html
index 77a948bdd..a9d2b8c59 100644
--- a/client/tools/api-docs/bonus.html
+++ b/client/tools/api-docs/bonus.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/check-answer.html b/client/tools/api-docs/check-answer.html
index 1c30755e6..19ed8ca66 100644
--- a/client/tools/api-docs/check-answer.html
+++ b/client/tools/api-docs/check-answer.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer" class="active fw-semibold" aria-current="page"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/frequency-list.html b/client/tools/api-docs/frequency-list.html
index 56f4c9252..96d965fb0 100644
--- a/client/tools/api-docs/frequency-list.html
+++ b/client/tools/api-docs/frequency-list.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/index.html b/client/tools/api-docs/index.html
index 65fb66ee6..9f348ec17 100644
--- a/client/tools/api-docs/index.html
+++ b/client/tools/api-docs/index.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
@@ -152,6 +154,16 @@ <h5 class="mt-4 md-2">Question Stats</h5>
                 </li>
             </ul>
 
+            <h5 class="mt-4 md-2">Leaderboard</h5>
+            <ul class="list-group list-group-flush">
+                <li class="list-group-item">
+                    <a href="./leaderboard">
+                        <div><code>GET</code> <code>/leaderboard</code></div>
+                    </a>
+                    <div>Rank every user by the number of questions they have heard. Requires a key.</div>
+                </li>
+            </ul>
+
             <h5 class="mt-4 md-2">Other</h5>
             <ul class="list-group list-group-flush">
                 <li class="list-group-item">
diff --git a/client/tools/api-docs/leaderboard.html b/client/tools/api-docs/leaderboard.html
new file mode 100644
index 000000000..19ac362d3
--- /dev/null
+++ b/client/tools/api-docs/leaderboard.html
@@ -0,0 +1,174 @@
+<!doctype html>
+<html lang="en">
+
+<head>
+    <title>QBReader - API Docs - Leaderboard</title>
+    <!--#include virtual="/ssi/head.html" -->
+    <meta name="description" content="The API documentation for QB Reader.">
+</head>
+
+<body>
+    <!--#include virtual="/ssi/nav.html" -->
+
+    <div class="container-xl mt-3 mb-4 row">
+        <div class="col-md-1"></div> <!-- empty column for some left margin -->
+        <!-- docs sidebar -->
+        <div class="d-none d-md-block col-2 h-100" id="docsSidebar">
+            <h4 class="offcanvas-title" id="docsSidebarLabel">API Reference</h4>
+            <div class="navbar-nav me-auto mb-2 mb-lg-0">
+                <a href="."><code>Overview</code></a>
+                <a href="./schemas"><code>Object Schemas</code></a>
+                <h5 class="mt-4 mb-2">Database</h5>
+                <a href="./query"><code>query</code></a>
+                <a href="./random-bonus"><code>random-bonus</code></a>
+                <a href="./random-tossup"><code>random-tossup</code></a>
+                <a href="./packet"><code>packet</code></a>
+                <a href="./num-packets"><code>num-packets</code></a>
+                <a href="./set-list"><code>set-list</code></a>
+                <a href="./bonus"><code>bonus</code></a>
+                <a href="./tossup"><code>tossup</code></a>
+                <a href="./frequency-list"><code>frequency-list</code></a>
+                <h5 class="mt-4 mb-2">Multiplayer</h5>
+                <a href="./multiplayer/room-list"><code>room-list</code></a>
+                <h5 class="mt-4 mb-2">Question Stats</h5>
+                <a href="./question-stats/bonus"><code>bonus</code></a>
+                <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard" class="active fw-semibold" aria-current="page"><code>leaderboard</code></a>
+                <h5 class="mt-4 mb-2">Other</h5>
+                <a href="./check-answer"><code>check-answer</code></a>
+                <a href="./random-name"><code>random-name</code></a>
+                <a href="./report-question"><code>report-question</code></a>
+            </div>
+        </div>
+
+        <div class="col-12 col-md-9">
+            <h3 class="md-4">
+                <div><code>GET</code> <code>qbreader.org/api/leaderboard</code></div>
+            </h3>
+
+            <p>
+                Rank every user by the number of questions they have heard.
+                Results are recomputed at most once every five minutes.
+            </p>
+
+            <div class="alert alert-warning">
+                <strong>This endpoint is not open.</strong> It returns every user's
+                username alongside their play stats, so it requires a key. Contact
+                a maintainer for access; unauthorized requests receive
+                <code>401</code>.
+            </div>
+
+            <a href="#parameters" class="text-body">
+                <h4 class="mt-4 md-2" id="parameters">Parameters</h4>
+            </a>
+            <ul class="list-group list-group-flush">
+                <li class="list-group-item">
+                    <div>
+                        <code>key</code><code class="text-muted">: string</code>
+                        <span class="text-muted">Required</span>
+                    </div>
+                    <div>
+                        The access key you were given. Requests with a missing or
+                        incorrect key receive <code>401</code>.
+                    </div>
+                </li>
+                <li class="list-group-item">
+                    <div>
+                        <code>limit</code><code class="text-muted">: number</code>
+                        <span class="text-muted">Optional</span>
+                    </div>
+                    <div>
+                        The maximum number of users to return.
+                        Defaults to <code>50</code>, and is clamped to the range 1&ndash;500.
+                    </div>
+                </li>
+                <li class="list-group-item">
+                    <div>
+                        <code>minQuestions</code><code class="text-muted">: number</code>
+                        <span class="text-muted">Optional</span>
+                    </div>
+                    <div>
+                        Exclude users who have heard fewer than this many questions.
+                        Defaults to <code>0</code>. Applied before <code>limit</code>.
+                    </div>
+                </li>
+            </ul>
+
+            <a href="#returns" class="text-body">
+                <h4 class="mt-4 md-2" id="returns">Returns</h4>
+            </a>
+            <div>
+                A JSON <code>object</code> with the following properties:
+            </div>
+            <ul class="list-group list-group-flush">
+                <li class="list-group-item">
+                    <div>
+                        <code>leaderboard</code><code class="text-muted">: Object[]</code>
+                    </div>
+                    <div>
+                        <p>
+                            An array of <code>objects</code>, sorted from most to least questions heard.
+                            Users who have been deleted are omitted.
+                        </p>
+                        <pre class="bg-dark p-3 rounded"><code class="text-light">{
+    _id: string                     // the user's id
+    username: string
+    tossupCount: number             // tossups heard
+    bonusCount: number              // bonuses heard
+    total: number                   // tossupCount + bonusCount
+    numCorrect: number              // tossups answered correctly
+    powers: number                  // tossups buzzed for 15 or more
+    tens: number                    // tossups buzzed for exactly 10
+    negs: number                    // tossups buzzed for a negative value
+    tossupPoints: number
+    bonusPoints: number
+    points: number                  // tossupPoints + bonusPoints
+    pptu: number                    // points per tossup heard
+    ppb: number                     // points per bonus heard
+    accuracy: number                // numCorrect / tossupCount, from 0 to 1
+    averageCorrectCelerity: number  // from 0 to 1; higher means an earlier buzz
+}</code></pre>
+                    </div>
+                </li>
+                <li class="list-group-item">
+                    <div>
+                        <code>count</code><code class="text-muted">: number</code>
+                    </div>
+                    <div>
+                        The number of users in <code>leaderboard</code>.
+                    </div>
+                </li>
+                <li class="list-group-item">
+                    <div>
+                        <code>generatedAt</code><code class="text-muted">: string</code>
+                    </div>
+                    <div>
+                        An ISO 8601 timestamp for when these rankings were computed.
+                    </div>
+                </li>
+            </ul>
+
+            <a href="#errors" class="text-body">
+                <h4 class="mt-4 md-2" id="errors">Errors</h4>
+            </a>
+            <ul class="list-group list-group-flush">
+                <li class="list-group-item">
+                    <code>401</code>
+                    <div>The <code>key</code> parameter is missing or incorrect.</div>
+                </li>
+                <li class="list-group-item">
+                    <code>503</code>
+                    <div>
+                        The rankings could not be computed. Returns a JSON
+                        <code>object</code> containing an <code>error</code> string.
+                    </div>
+                </li>
+            </ul>
+        </div>
+    </div>
+
+
+</body>
+
+</html>
diff --git a/client/tools/api-docs/multiplayer/room-list.html b/client/tools/api-docs/multiplayer/room-list.html
index d7f2d3d4a..afbf85da4 100644
--- a/client/tools/api-docs/multiplayer/room-list.html
+++ b/client/tools/api-docs/multiplayer/room-list.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="../question-stats/bonus"><code>bonus</code></a>
                 <a href="../question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="../leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="../check-answer"><code>check-answer</code></a>
                 <a href="../random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/num-packets.html b/client/tools/api-docs/num-packets.html
index 3f36c7424..7b3895f83 100644
--- a/client/tools/api-docs/num-packets.html
+++ b/client/tools/api-docs/num-packets.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/packet.html b/client/tools/api-docs/packet.html
index 3b2b7219f..a74a448aa 100644
--- a/client/tools/api-docs/packet.html
+++ b/client/tools/api-docs/packet.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/query.html b/client/tools/api-docs/query.html
index 629223701..ca75a4905 100644
--- a/client/tools/api-docs/query.html
+++ b/client/tools/api-docs/query.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/question-stats/bonus.html b/client/tools/api-docs/question-stats/bonus.html
index 311de0eb5..12b0aa5f7 100644
--- a/client/tools/api-docs/question-stats/bonus.html
+++ b/client/tools/api-docs/question-stats/bonus.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="../question-stats/bonus" class="active fw-semibold" aria-current="page"><code>bonus</code></a>
                 <a href="../question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="../leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="../check-answer"><code>check-answer</code></a>
                 <a href="../random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/question-stats/tossup.html b/client/tools/api-docs/question-stats/tossup.html
index e38641664..b5d145a33 100644
--- a/client/tools/api-docs/question-stats/tossup.html
+++ b/client/tools/api-docs/question-stats/tossup.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="../question-stats/bonus"><code>bonus</code></a>
                 <a href="../question-stats/tossup" class="active fw-semibold" aria-current="page"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="../leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="../check-answer"><code>check-answer</code></a>
                 <a href="../random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/random-bonus.html b/client/tools/api-docs/random-bonus.html
index 1f16b5c8f..25990946e 100644
--- a/client/tools/api-docs/random-bonus.html
+++ b/client/tools/api-docs/random-bonus.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/random-name.html b/client/tools/api-docs/random-name.html
index 371209a7a..c9a3e441e 100644
--- a/client/tools/api-docs/random-name.html
+++ b/client/tools/api-docs/random-name.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name" class="active fw-semibold" aria-current="page"><code>random-name</code></a>
diff --git a/client/tools/api-docs/random-tossup.html b/client/tools/api-docs/random-tossup.html
index 6ee5844f6..9ec7ad960 100644
--- a/client/tools/api-docs/random-tossup.html
+++ b/client/tools/api-docs/random-tossup.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/report-question.html b/client/tools/api-docs/report-question.html
index 9a41a4489..037904037 100644
--- a/client/tools/api-docs/report-question.html
+++ b/client/tools/api-docs/report-question.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/schemas/index.html b/client/tools/api-docs/schemas/index.html
index ee06cf52d..d078030cd 100644
--- a/client/tools/api-docs/schemas/index.html
+++ b/client/tools/api-docs/schemas/index.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="../question-stats/bonus"><code>bonus</code></a>
                 <a href="../question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="../leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="../check-answer"><code>check-answer</code></a>
                 <a href="../random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/set-list.html b/client/tools/api-docs/set-list.html
index f185d160b..16912e79b 100644
--- a/client/tools/api-docs/set-list.html
+++ b/client/tools/api-docs/set-list.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/client/tools/api-docs/tossup.html b/client/tools/api-docs/tossup.html
index 3553525c4..8cd240bdb 100644
--- a/client/tools/api-docs/tossup.html
+++ b/client/tools/api-docs/tossup.html
@@ -33,6 +33,8 @@ <h5 class="mt-4 mb-2">Multiplayer</h5>
                 <h5 class="mt-4 mb-2">Question Stats</h5>
                 <a href="./question-stats/bonus"><code>bonus</code></a>
                 <a href="./question-stats/tossup"><code>tossup</code></a>
+                <h5 class="mt-4 mb-2">Leaderboard</h5>
+                <a href="./leaderboard"><code>leaderboard</code></a>
                 <h5 class="mt-4 mb-2">Other</h5>
                 <a href="./check-answer"><code>check-answer</code></a>
                 <a href="./random-name"><code>random-name</code></a>
diff --git a/database/account-info/leaderboard.js b/database/account-info/leaderboard.js
index acf8fea7b..3cd8b2464 100644
--- a/database/account-info/leaderboard.js
+++ b/database/account-info/leaderboard.js
@@ -5,41 +5,84 @@ const CACHE_TTL = 5 * 60 * 1000; // 5 minutes
 let cachedOverall = null;
 let cachedAt = 0;
 
+/**
+ * @typedef {Object} LeaderboardRow
+ * @property {ObjectId} _id - the user's _id
+ * @property {String} username
+ * @property {Number} tossupCount - tossups heard
+ * @property {Number} bonusCount - bonuses heard
+ * @property {Number} total - tossupCount + bonusCount
+ * @property {Number} numCorrect - tossups answered correctly
+ * @property {Number} powers - tossups buzzed for 15 or more
+ * @property {Number} tens - tossups buzzed for exactly 10
+ * @property {Number} negs - tossups buzzed for a negative value
+ * @property {Number} tossupPoints
+ * @property {Number} bonusPoints
+ * @property {Number} points - tossupPoints + bonusPoints
+ * @property {Number} pptu - points per tossup heard
+ * @property {Number} ppb - points per bonus heard
+ * @property {Number} accuracy - numCorrect / tossupCount, in [0, 1]
+ * @property {Number} averageCorrectCelerity - in [0, 1]; higher means an earlier buzz
+ */
+
+/**
+ * Rank every user by the number of questions they have heard.
+ * Results are cached for five minutes, since the underlying aggregations
+ * unwind the entirety of per-tossup-data and per-bonus-data.
+ * @param {Number} [limit] - the maximum number of rows to return; all rows if falsy.
+ * @returns {Promise<LeaderboardRow[]>} sorted from most to least questions heard.
+ */
 export default async function leaderboard (limit) {
-  if (cachedOverall && Date.now() - cachedAt < CACHE_TTL) {
-    return cachedOverall.slice(0, limit);
+  if (!cachedOverall || Date.now() - cachedAt >= CACHE_TTL) {
+    const tossupLeaderboard = await tossupHelper();
+    const bonusLeaderboard = await bonusHelper();
+    const overall = mergeTwoSortedArrays(
+      tossupLeaderboard,
+      bonusLeaderboard,
+      (document) => document.username,
+      combineRows
+    );
+    // sort from most to least
+    overall.sort((a, b) => b.total - a.total);
+    cachedOverall = overall;
+    cachedAt = Date.now();
   }
 
-  const tossupLeaderboard = await helper('tossup');
-  const bonusLeaderboard = await helper('bonus');
-  const overall = mergeTwoSortedArrays(
-    tossupLeaderboard,
-    bonusLeaderboard,
-    (document) => document.username,
-    (document1, document2) => ({ _id: document1._id, username: document1.username, tossupCount: document1.tossupCount, bonusCount: document2.bonusCount, total: document1.total + document2.total })
-  );
-  // sort from most to least
-  overall.sort((a, b) => b.total - a.total);
-  cachedOverall = overall;
-  cachedAt = Date.now();
-  return overall.slice(0, limit);
+  return limit ? cachedOverall.slice(0, limit) : cachedOverall;
 }
 
 /**
- *
- * @param {'tossup' | 'bonus'} type - the type of questions to filter by
- * @returns
+ * When the currently cached leaderboard was computed.
+ * @returns {Date | null} null if the leaderboard has not been computed yet.
  */
-async function helper (type = 'tossup') {
-  const aggregation = [
-    { $unwind: '$data' },
-    { $addFields: { user_id: '$data.user_id' } },
-    {
-      $group: {
-        _id: '$user_id',
-        count: { $sum: 1 }
-      }
-    },
+export function lastGeneratedAt () {
+  return cachedOverall ? new Date(cachedAt) : null;
+}
+
+/**
+ * Combine a user's tossup-only row with their bonus-only row.
+ * @param {LeaderboardRow} tossupRow
+ * @param {LeaderboardRow} bonusRow
+ * @returns {LeaderboardRow}
+ */
+function combineRows (tossupRow, bonusRow) {
+  return {
+    ...tossupRow,
+    bonusCount: bonusRow.bonusCount,
+    bonusPoints: bonusRow.bonusPoints,
+    ppb: bonusRow.ppb,
+    total: tossupRow.total + bonusRow.total,
+    points: tossupRow.points + bonusRow.points
+  };
+}
+
+/**
+ * Look the username up for each grouped user_id and drop users that no longer exist.
+ * @param {Object} projection - the fields to keep alongside _id and username.
+ * @returns {Object[]} the trailing stages shared by both aggregations.
+ */
+function usernameStages (projection) {
+  return [
     {
       $lookup: {
         from: 'users',
@@ -50,22 +93,106 @@ async function helper (type = 'tossup') {
     },
     {
       $project: {
-        username: { $arrayElemAt: ['$user.username', 0] },
         _id: 1,
-        total: '$count'
+        username: { $arrayElemAt: ['$user.username', 0] },
+        ...projection
       }
     },
-    { $sort: { username: 1 } }
+    // users deleted since their buzzes were recorded have no username to rank
+    { $match: { username: { $ne: null } } }
   ];
+}
 
-  switch (type) {
-    case 'tossup': {
-      const results = await perTossupData.aggregate(aggregation).toArray();
-      return results.map((result) => ({ ...result, tossupCount: result.total, bonusCount: 0 }));
-    }
-    case 'bonus': {
-      const results = await perBonusData.aggregate(aggregation).toArray();
-      return results.map((result) => ({ ...result, tossupCount: 0, bonusCount: result.total }));
-    }
-  }
+/**
+ * mergeTwoSortedArrays compares usernames with < and >, so both inputs must be
+ * sorted by that same comparison. Sorting here rather than with a $sort stage
+ * keeps the ordering in one place and avoids an unindexed server-side sort.
+ * @param {LeaderboardRow} a
+ * @param {LeaderboardRow} b
+ * @returns {Number}
+ */
+function byUsername (a, b) {
+  if (a.username < b.username) { return -1; }
+  if (a.username > b.username) { return 1; }
+  return 0;
+}
+
+/**
+ * @returns {Promise<LeaderboardRow[]>} one row per user, with the bonus fields zeroed.
+ */
+async function tossupHelper () {
+  const results = await perTossupData.aggregate([
+    { $unwind: '$data' },
+    { $match: { 'data.user_id': { $ne: null } } },
+    {
+      $group: {
+        _id: '$data.user_id',
+        tossupCount: { $sum: 1 },
+        numCorrect: { $sum: { $cond: ['$data.isCorrect', 1, 0] } },
+        powers: { $sum: { $cond: [{ $gte: ['$data.pointValue', 15] }, 1, 0] } },
+        tens: { $sum: { $cond: [{ $eq: ['$data.pointValue', 10] }, 1, 0] } },
+        negs: { $sum: { $cond: [{ $lt: ['$data.pointValue', 0] }, 1, 0] } },
+        tossupPoints: { $sum: '$data.pointValue' },
+        totalCorrectCelerity: { $sum: { $cond: ['$data.isCorrect', '$data.celerity', 0] } }
+      }
+    },
+    ...usernameStages({
+      tossupCount: 1,
+      numCorrect: 1,
+      powers: 1,
+      tens: 1,
+      negs: 1,
+      tossupPoints: 1,
+      pptu: { $cond: ['$tossupCount', { $divide: ['$tossupPoints', '$tossupCount'] }, 0] },
+      accuracy: { $cond: ['$tossupCount', { $divide: ['$numCorrect', '$tossupCount'] }, 0] },
+      averageCorrectCelerity: { $cond: ['$numCorrect', { $divide: ['$totalCorrectCelerity', '$numCorrect'] }, 0] }
+    })
+  ]).toArray();
+
+  return results.map((result) => ({
+    ...result,
+    bonusCount: 0,
+    bonusPoints: 0,
+    ppb: 0,
+    total: result.tossupCount,
+    points: result.tossupPoints
+  })).sort(byUsername);
+}
+
+/**
+ * @returns {Promise<LeaderboardRow[]>} one row per user, with the tossup fields zeroed.
+ */
+async function bonusHelper () {
+  const results = await perBonusData.aggregate([
+    { $unwind: '$data' },
+    { $match: { 'data.user_id': { $ne: null } } },
+    { $addFields: { pointsThisBonus: { $sum: '$data.pointsPerPart' } } },
+    {
+      $group: {
+        _id: '$data.user_id',
+        bonusCount: { $sum: 1 },
+        bonusPoints: { $sum: '$pointsThisBonus' }
+      }
+    },
+    ...usernameStages({
+      bonusCount: 1,
+      bonusPoints: 1,
+      ppb: { $cond: ['$bonusCount', { $divide: ['$bonusPoints', '$bonusCount'] }, 0] }
+    })
+  ]).toArray();
+
+  return results.map((result) => ({
+    ...result,
+    tossupCount: 0,
+    numCorrect: 0,
+    powers: 0,
+    tens: 0,
+    negs: 0,
+    tossupPoints: 0,
+    pptu: 0,
+    accuracy: 0,
+    averageCorrectCelerity: 0,
+    total: result.bonusCount,
+    points: result.bonusPoints
+  })).sort(byUsername);
 }
diff --git a/routes/api/index.js b/routes/api/index.js
index 2918ac137..173e13588 100644
--- a/routes/api/index.js
+++ b/routes/api/index.js
@@ -4,6 +4,7 @@ import checkAnswerRouter from './check-answer.js';
 import dbExplorerRouter from './db-explorer/index.js';
 import frequencyListRouter from './frequency-list.js';
 import geowordRouter from './geoword/index.js';
+import leaderboardRouter from './leaderboard.js';
 import multiplayerRouter from './multiplayer/index.js';
 import numPacketsRouter from './num-packets.js';
 import packetRouter from './packet.js';
@@ -51,6 +52,7 @@ router.use('/check-answer', checkAnswerRouter);
 router.use('/db-explorer', dbExplorerRouter);
 router.use('/frequency-list', frequencyListRouter);
 router.use('/geoword', geowordRouter);
+router.use('/leaderboard', leaderboardRouter);
 router.use('/multiplayer', multiplayerRouter);
 router.use('/num-packets', numPacketsRouter);
 router.use('/packet', packetRouter);
diff --git a/routes/api/leaderboard.js b/routes/api/leaderboard.js
new file mode 100644
index 000000000..e64238f2c
--- /dev/null
+++ b/routes/api/leaderboard.js
@@ -0,0 +1,71 @@
+import getLeaderboard, { lastGeneratedAt } from '../../database/account-info/leaderboard.js';
+import validateInt from '../validators/int.js';
+
+import { createHash, timingSafeEqual } from 'crypto';
+import { Router } from 'express';
+
+// matches the five minute cache in database/account-info/leaderboard.js
+const MAX_AGE_SECONDS = 300;
+
+const router = Router();
+
+/**
+ * This endpoint returns every user's username and play stats, so it is gated
+ * behind a shared secret rather than served publicly. Set LEADERBOARD_KEY in
+ * the environment and share it only with sites you want to have access;
+ * requests without a matching ?key= are rejected. If LEADERBOARD_KEY is
+ * unset, every request is rejected rather than the endpoint quietly
+ * becoming public.
+ * @param {unknown} providedKey - req.query.key; unvalidated, so may be anything
+ * @returns {boolean}
+ */
+function isAuthorized (providedKey) {
+  const expectedKey = process.env.LEADERBOARD_KEY;
+  if (!expectedKey || typeof providedKey !== 'string') { return false; }
+
+  const expected = Buffer.from(expectedKey);
+  const provided = Buffer.from(providedKey);
+  // encode as a fixed-length hash first so timingSafeEqual doesn't throw
+  // and comparing keys of different lengths doesn't leak the true length
+  return timingSafeEqual(
+    createHash('sha256').update(expected).digest(),
+    createHash('sha256').update(provided).digest()
+  );
+}
+
+router.get('/', async (req, res) => {
+  if (!isAuthorized(req.query.key)) {
+    res.sendStatus(401);
+    return;
+  }
+
+  req.query = validateInt(req.query, 'limit', { defaultValue: 50, lowerBound: 1, upperBound: 500 });
+  req.query = validateInt(req.query, 'minQuestions', { defaultValue: 0, lowerBound: 0 });
+  const { limit, minQuestions } = req.query;
+
+  // express 4 does not forward rejected promises to the error handler,
+  // so an unhandled rejection here would take down the process
+  let everyone;
+  try {
+    everyone = await getLeaderboard();
+  } catch (error) {
+    console.error('GET /api/leaderboard:', error);
+    res.status(503).json({ error: 'The leaderboard is temporarily unavailable. Try again shortly.' });
+    return;
+  }
+
+  const leaderboard = everyone
+    .filter((row) => row.total >= minQuestions)
+    .slice(0, limit);
+
+  // private: a shared/CDN cache must not serve this response to a caller
+  // that did not supply its own key
+  res.set('Cache-Control', `private, max-age=${MAX_AGE_SECONDS}`);
+  res.json({
+    leaderboard,
+    count: leaderboard.length,
+    generatedAt: lastGeneratedAt()
+  });
+});
+
+export default router;