diff --git a/js/nostr.js b/js/nostr.js
index dd97a339..79f12ef1 100644
--- a/js/nostr.js
+++ b/js/nostr.js
@@ -11,6 +11,7 @@ import {
   WATCH_HISTORY_FETCH_EVENT_LIMIT,
   WATCH_HISTORY_CACHE_TTL_MS,
   VIEW_COUNT_DEDUPE_WINDOW_SECONDS,
+  VIEW_COUNT_BACKFILL_MAX_DAYS,
 } from "./config.js";
 import {
   ACCEPT_LEGACY_V1,
@@ -3052,8 +3053,51 @@ class NostrClient {
   }
 
   async countVideoViewEvents(pointer, options = {}) {
+    const relayList =
+      Array.isArray(options?.relays) && options.relays.length
+        ? options.relays
+        : undefined;
+
+    const fallbackListOptions = (() => {
+      const listOptions = {};
+
+      if (relayList) {
+        listOptions.relays = relayList;
+      }
+
+      if (Number.isFinite(options?.since)) {
+        listOptions.since = Math.floor(options.since);
+      } else {
+        const horizonDaysRaw = Number(VIEW_COUNT_BACKFILL_MAX_DAYS);
+        const horizonDays = Number.isFinite(horizonDaysRaw)
+          ? Math.max(0, Math.floor(horizonDaysRaw))
+          : 0;
+        if (horizonDays > 0) {
+          const secondsPerDay = 86_400;
+          const nowSeconds = Math.floor(Date.now() / 1000);
+          const fallbackSinceSeconds = Math.max(
+            0,
+            nowSeconds - horizonDays * secondsPerDay
+          );
+          listOptions.since = Math.floor(fallbackSinceSeconds);
+        }
+      }
+
+      if (Number.isFinite(options?.until)) {
+        listOptions.until = Math.floor(options.until);
+      }
+
+      if (Number.isFinite(options?.limit) && options.limit > 0) {
+        listOptions.limit = Math.floor(options.limit);
+      }
+
+      return listOptions;
+    })();
+
     if (!this.pool) {
-      const events = await this.listVideoViewEvents(pointer, options);
+      const events = await this.listVideoViewEvents(pointer, {
+        ...fallbackListOptions,
+      });
       return {
         total: Array.isArray(events) ? events.length : 0,
         perRelay: [],
@@ -3067,9 +3111,6 @@ class NostrClient {
     if (!pointerFilter || typeof pointerFilter !== "object") {
       throw new Error("Invalid video pointer supplied for view lookup.");
     }
-    const relayList = Array.isArray(options?.relays) && options.relays.length
-      ? options.relays
-      : undefined;
 
     const signal = options?.signal;
     const normalizeAbortError = () => {
@@ -3122,7 +3163,7 @@ class NostrClient {
         : null;
 
     const listPromise = this.listVideoViewEvents(pointer, {
-      relays: relayList,
+      ...fallbackListOptions,
     });
 
     const events = abortPromise
diff --git a/tests/nostr-count-fallback.test.mjs b/tests/nostr-count-fallback.test.mjs
new file mode 100644
index 00000000..fc7a3487
--- /dev/null
+++ b/tests/nostr-count-fallback.test.mjs
@@ -0,0 +1,151 @@
+// Run with: node tests/nostr-count-fallback.test.mjs
+
+import "./test-helpers/setup-localstorage.mjs";
+import assert from "node:assert/strict";
+
+if (typeof globalThis.window === "undefined") {
+  globalThis.window = {};
+}
+
+if (!globalThis.window.NostrTools) {
+  globalThis.window.NostrTools = {};
+}
+
+const { VIEW_COUNT_BACKFILL_MAX_DAYS } = await import("../js/config.js");
+const { nostrClient } = await import("../js/nostr.js");
+
+const NostrClient = nostrClient.constructor;
+
+async function withFrozenTime(timestampSeconds, callback) {
+  const originalNow = Date.now;
+  Date.now = () => timestampSeconds * 1000;
+  try {
+    return await callback();
+  } finally {
+    Date.now = originalNow;
+  }
+}
+
+function getConfiguredHorizonDays() {
+  const horizonDaysRaw = Number(VIEW_COUNT_BACKFILL_MAX_DAYS);
+  return Number.isFinite(horizonDaysRaw)
+    ? Math.max(0, Math.floor(horizonDaysRaw))
+    : 0;
+}
+
+async function testFallbackAddsDefaultSinceWhenPoolMissing() {
+  const client = new NostrClient();
+  client.pool = null;
+
+  const pointer = { type: "e", value: "count-fallback-default" };
+  const calls = [];
+  client.listVideoViewEvents = async (_, options = {}) => {
+    calls.push({ ...options });
+    return [];
+  };
+
+  const horizonDays = getConfiguredHorizonDays();
+
+  const nowSeconds = 1_700_000_000;
+  await withFrozenTime(nowSeconds, async () => {
+    const result = await client.countVideoViewEvents(pointer, {});
+    assert.equal(calls.length, 1, "fallback should issue a single list query");
+    const [{ since }] = calls;
+    if (horizonDays > 0) {
+      const expectedSince = Math.max(0, nowSeconds - horizonDays * 86_400);
+      assert.equal(
+        since,
+        expectedSince,
+        "fallback list should clamp history to the configured horizon"
+      );
+    } else {
+      assert.equal(
+        Object.prototype.hasOwnProperty.call(calls[0], "since"),
+        false,
+        "without a configured horizon the fallback should avoid forcing a since filter"
+      );
+    }
+    assert.equal(result.fallback, true, "fallback branch should be flagged");
+  });
+}
+
+async function testFallbackHonorsCallerOverrides() {
+  const client = new NostrClient();
+  client.pool = null;
+
+  const pointer = { type: "e", value: "count-fallback-overrides" };
+  let receivedOptions = null;
+  client.listVideoViewEvents = async (_, options = {}) => {
+    receivedOptions = { ...options };
+    return [];
+  };
+
+  const overrides = {
+    since: 1_234_567,
+    until: 1_235_000,
+    limit: 42,
+  };
+
+  await client.countVideoViewEvents(pointer, overrides);
+
+  assert.ok(receivedOptions, "fallback should forward overrides to list");
+  assert.equal(
+    receivedOptions.since,
+    Math.floor(overrides.since),
+    "caller supplied since should be preserved"
+  );
+  assert.equal(
+    receivedOptions.until,
+    Math.floor(overrides.until),
+    "caller supplied until should be preserved"
+  );
+  assert.equal(
+    receivedOptions.limit,
+    Math.floor(overrides.limit),
+    "caller supplied limit should be preserved"
+  );
+}
+
+async function testFallbackAfterCountFailureUsesDefaultWindow() {
+  const client = new NostrClient();
+  client.pool = {};
+  client.countEventsAcrossRelays = async () => {
+    throw new Error("count failed");
+  };
+
+  const pointer = { type: "e", value: "count-fallback-error" };
+  let receivedOptions = null;
+  client.listVideoViewEvents = async (_, options = {}) => {
+    receivedOptions = { ...options };
+    return [];
+  };
+
+  const horizonDays = getConfiguredHorizonDays();
+
+  const nowSeconds = 1_800_000_000;
+  await withFrozenTime(nowSeconds, async () => {
+    await client.countVideoViewEvents(pointer, {});
+  });
+
+  assert.ok(receivedOptions, "fallback should invoke the list helper");
+  if (horizonDays > 0) {
+    const expectedSince = Math.max(0, nowSeconds - horizonDays * 86_400);
+    assert.equal(
+      receivedOptions.since,
+      expectedSince,
+      "COUNT fallback should restrict scans to the configured horizon"
+    );
+  } else {
+    assert.equal(
+      Object.prototype.hasOwnProperty.call(receivedOptions, "since"),
+      false,
+      "COUNT fallback should avoid forcing a since filter when no horizon is set"
+    );
+  }
+}
+
+await testFallbackAddsDefaultSinceWhenPoolMissing();
+await testFallbackHonorsCallerOverrides();
+await testFallbackAfterCountFailureUsesDefaultWindow();
+
+console.log("nostr COUNT fallback tests completed successfully.");