diff --git a/components/edit-video-modal.html b/components/edit-video-modal.html
index 5fac2a24..fa6d9519 100644
--- a/components/edit-video-modal.html
+++ b/components/edit-video-modal.html
@@ -537,6 +537,9 @@
                   Add hashtag
                 </button>
               </div>
+              <p class="text-xs text-gray-400">
+                Enter keywords; leading <code>#</code> characters are stripped automatically when saving.
+              </p>
               <div id="editNip71HashtagList" class="space-y-2" data-nip71-list="t"></div>
               <template id="editNip71HashtagTemplate" data-nip71-template="t">
                 <div class="flex items-center gap-2" data-nip71-entry="t">
diff --git a/components/upload-modal.html b/components/upload-modal.html
index 6fc82488..d44f7976 100644
--- a/components/upload-modal.html
+++ b/components/upload-modal.html
@@ -599,14 +599,16 @@
                     Add hashtag
                   </button>
                 </div>
-                <p class="text-xs text-gray-400">Enter bare keywords without the <code>#</code> prefix.</p>
+                <p class="text-xs text-gray-400">
+                  Enter keywords; leading <code>#</code> characters are stripped automatically when saving.
+                </p>
                 <div id="nip71HashtagList" class="space-y-2" data-nip71-list="t"></div>
                 <template id="nip71HashtagTemplate" data-nip71-template="t">
                   <div class="flex items-center gap-2" data-nip71-entry="t">
                     <input
                       type="text"
                       data-nip71-field="value"
-                      placeholder="nostr"
+                      placeholder="#nostr"
                       class="flex-1 rounded-md border border-gray-700 bg-gray-800 px-3 py-2 text-gray-100 focus:border-blue-500 focus:ring-blue-500"
                     />
                     <button
diff --git a/js/ui/components/nip71FormManager.js b/js/ui/components/nip71FormManager.js
index a325a5e1..05f6a43f 100644
--- a/js/ui/components/nip71FormManager.js
+++ b/js/ui/components/nip71FormManager.js
@@ -227,8 +227,12 @@ export class Nip71FormManager {
       this.setFieldValue(entry, "thumbnail", value.thumbnail);
     });
 
-    this.hydrateRepeater(key, "t", metadata.hashtags ?? metadata.t, (entry, value) => {
-      this.setFieldValue(entry, "value", value);
+    const sanitizedHashtags = this.sanitizeHashtags(
+      metadata.hashtags ?? metadata.t,
+      { dedupe: true }
+    );
+    this.hydrateRepeater(key, "t", sanitizedHashtags, (entry, value) => {
+      this.setFieldValue(entry, "value", this.renderHashtagValue(value));
     });
 
     this.hydrateRepeater(
@@ -337,10 +341,13 @@ export class Nip71FormManager {
       return hasContent ? segment : null;
     });
 
-    const hashtags = this.collectRepeaterValues(key, "t", (entry) => {
-      const value = this.getFieldValue(entry, "value");
-      return value || null;
-    });
+    const hashtags = this.sanitizeHashtags(
+      this.collectRepeaterValues(key, "t", (entry) => {
+        const value = this.getFieldValue(entry, "value");
+        return value || null;
+      }),
+      { dedupe: true }
+    );
 
     const participants = this.collectRepeaterValues(key, "p", (entry) => {
       const participant = {
@@ -402,6 +409,58 @@ export class Nip71FormManager {
     return results;
   }
 
+  sanitizeHashtags(values, { dedupe = false } = {}) {
+    if (!Array.isArray(values)) {
+      return [];
+    }
+
+    const results = [];
+    const seen = new Set();
+
+    values.forEach((value) => {
+      const sanitized = this.sanitizeHashtagValue(value);
+      if (!sanitized) {
+        return;
+      }
+      const dedupeKey = sanitized.toLowerCase();
+      if (dedupe) {
+        if (seen.has(dedupeKey)) {
+          return;
+        }
+        seen.add(dedupeKey);
+      }
+      results.push(sanitized);
+    });
+
+    return results;
+  }
+
+  sanitizeHashtagValue(value) {
+    if (typeof value === "number") {
+      value = Number.isFinite(value) ? `${value}` : "";
+    }
+    if (typeof value !== "string") {
+      value = `${value ?? ""}`;
+    }
+
+    const trimmed = value.trim();
+    if (!trimmed) {
+      return "";
+    }
+
+    const withoutHash = trimmed.replace(/^#+/, "").trim();
+    if (!withoutHash) {
+      return "";
+    }
+
+    return withoutHash.toLowerCase();
+  }
+
+  renderHashtagValue(value) {
+    const sanitized = this.sanitizeHashtagValue(value);
+    return sanitized ? `#${sanitized}` : "";
+  }
+
   collectNestedValues(entry, nestedKey) {
     if (!entry || !nestedKey) {
       return [];
diff --git a/tests/nip71-form-manager.test.mjs b/tests/nip71-form-manager.test.mjs
new file mode 100644
index 00000000..d121056b
--- /dev/null
+++ b/tests/nip71-form-manager.test.mjs
@@ -0,0 +1,74 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { JSDOM } from "jsdom";
+
+import { Nip71FormManager } from "../js/ui/components/nip71FormManager.js";
+
+function createManagerWithSection(html) {
+  const dom = new JSDOM(html);
+  const document = dom.window.document;
+  const manager = new Nip71FormManager();
+  const sectionRoot = document.querySelector("#nip71-section-root");
+  manager.registerSection("test", sectionRoot);
+  return { manager, document };
+}
+
+test("collectSection sanitizes and deduplicates hashtags", () => {
+  const { manager } = createManagerWithSection(`
+    <form id="nip71-section-root">
+      <section data-nip71-repeater="t">
+        <div data-nip71-list="t">
+          <div data-nip71-entry="t" data-nip71-primary="true">
+            <input data-nip71-field="value" value="  #Nostr  " />
+          </div>
+          <div data-nip71-entry="t">
+            <input data-nip71-field="value" value="#nostr" />
+          </div>
+          <div data-nip71-entry="t">
+            <input data-nip71-field="value" value="  #Video  " />
+          </div>
+        </div>
+        <template data-nip71-template="t">
+          <div data-nip71-entry="t">
+            <input data-nip71-field="value" />
+          </div>
+        </template>
+      </section>
+    </form>
+  `);
+
+  const collected = manager.collectSection("test");
+  assert.deepEqual(collected.hashtags, ["nostr", "video"]);
+});
+
+test("hydrateSection renders sanitized hashtags with prefix", () => {
+  const { manager, document } = createManagerWithSection(`
+    <form id="nip71-section-root">
+      <section data-nip71-repeater="t">
+        <div data-nip71-list="t">
+          <div data-nip71-entry="t" data-nip71-primary="true">
+            <input data-nip71-field="value" value="" />
+          </div>
+        </div>
+        <template data-nip71-template="t">
+          <div data-nip71-entry="t">
+            <input data-nip71-field="value" />
+          </div>
+        </template>
+      </section>
+    </form>
+  `);
+
+  manager.hydrateSection("test", {
+    hashtags: ["  #Nostr  ", "#Nostr", "  #Video  " ],
+  });
+
+  const entries = Array.from(
+    document.querySelectorAll('[data-nip71-entry="t"]')
+  );
+  assert.equal(entries.length, 2);
+  const values = entries.map((entry) =>
+    entry.querySelector('[data-nip71-field="value"]').value
+  );
+  assert.deepEqual(values, ["#nostr", "#video"]);
+});