diff --git a/src/app/component/plugin/plugin.component.html b/src/app/component/plugin/plugin.component.html
index 6ffbce3b9..19a84c7ac 100644
--- a/src/app/component/plugin/plugin.component.html
+++ b/src/app/component/plugin/plugin.component.html
@@ -23,6 +23,10 @@
     </ng-template>
     <a class="fake-link"
        (click)="download()" i18n>download</a>
+    @if (plugin.config?.export) {
+      <a class="fake-link"
+         (click)="export()" i18n>export</a>
+    }
     <a *ngIf="!deleting && store.account.admin"
        class="fake-link"
        (click)="deleting = true" i18n>delete</a>
diff --git a/src/app/component/plugin/plugin.component.ts b/src/app/component/plugin/plugin.component.ts
index 851b51b2e..7c64d892c 100644
--- a/src/app/component/plugin/plugin.component.ts
+++ b/src/app/component/plugin/plugin.component.ts
@@ -9,8 +9,9 @@ import { Plugin, writePlugin } from '../../model/plugin';
 import { tagDeleteNotice } from "../../mods/delete";
 import { AdminService } from '../../service/admin.service';
 import { PluginService } from '../../service/api/plugin.service';
+import { ModService } from '../../service/mod.service';
 import { Store } from '../../store/store';
-import { downloadTag } from '../../util/download';
+import { downloadPluginExport, downloadTag } from '../../util/download';
 import { scrollToFirstInvalid } from '../../util/form';
 import { printError } from '../../util/http';
 
@@ -39,6 +40,7 @@ export class PluginComponent implements OnInit {
   schemaErrors: string[] = [];
 
   constructor(
+    private mod: ModService,
     public admin: AdminService,
     public store: Store,
     private plugins: PluginService,
@@ -150,4 +152,8 @@ export class PluginComponent implements OnInit {
   download() {
     downloadTag(writePlugin(this.plugin));
   }
+
+  export() {
+    downloadPluginExport(this.plugin, this.mod.exportHtml(this.plugin));
+  }
 }
diff --git a/src/app/model/plugin.ts b/src/app/model/plugin.ts
index cdb2b7bfc..d26538f1e 100644
--- a/src/app/model/plugin.ts
+++ b/src/app/model/plugin.ts
@@ -57,6 +57,10 @@ export interface Plugin extends Config {
      * Disable the editor and use the viewer to edit.
      */
     editingViewer?: boolean;
+    /**
+     * This plugin can be exported to a self-contained html file.
+     */
+    export?: boolean,
     /**
      * Show plugin as signature for existing tag.
      */
diff --git a/src/app/model/tag.ts b/src/app/model/tag.ts
index bab53dc7a..828323b19 100644
--- a/src/app/model/tag.ts
+++ b/src/app/model/tag.ts
@@ -5,6 +5,7 @@ import { Schema } from 'jtd';
 import { defer, isEqual, omitBy, uniqWith } from 'lodash-es';
 import { toJS } from 'mobx';
 import * as moment from 'moment';
+import { MomentInput } from 'moment/moment';
 import { v4 as uuid } from 'uuid';
 import { hasTag, prefix } from '../util/tag';
 import { filterModels } from '../util/zip';
@@ -352,7 +353,7 @@ Handlebars.registerHelper('defer', (el: Element, fn: () => {}) => {
   }
 });
 
-Handlebars.registerHelper('fromNow', value => moment(value).fromNow());
+Handlebars.registerHelper('fromNow', (value: MomentInput) => moment(value).fromNow());
 
 Handlebars.registerHelper('response', (ref: Ref, value: string) => {
   return ref.metadata?.userUrls?.includes(value);
diff --git a/src/app/mods/ninga-triangle.ts b/src/app/mods/ninga-triangle.ts
index f5536a18d..f036644cf 100644
--- a/src/app/mods/ninga-triangle.ts
+++ b/src/app/mods/ninga-triangle.ts
@@ -15,14 +15,15 @@ export const ninjaTrianglePlugin: Plugin = {
     submitText: true,
     add: true,
     genId: true,
+    export: true,
     generated: $localize`Generated by jasper-ui ${moment().toISOString()}`,
     description: $localize`Create a Japanese Triangle and show the longest Ninja Path.`,
     aiInstructions: ` # plugin/ninja.triangle
-    Let $n$ be a positive integer. A *Japanese triangle* consists of $1 + 2 + \\ldots + n$ circles arranged in an
-    equilateral triangular shape such that for each $i = 1, 2, \\ldots, n$, the $i$th row contains exactly $i$ circles,
-    exactly one of which is coloured red. A *ninja path* in a Japanese triangle is a sequence of $n$ circles obtained by
-    starting in the top row, then repeatedly going from a circle to one of the two circles immediately below it and
-    finishing in the bottom row. Here is an example of a Japanese triangle with $n = 6$.
+Let $n$ be a positive integer. A *Japanese triangle* consists of $1 + 2 + \\ldots + n$ circles arranged in an
+equilateral triangular shape such that for each $i = 1, 2, \\ldots, n$, the $i$th row contains exactly $i$ circles,
+exactly one of which is coloured red. A *ninja path* in a Japanese triangle is a sequence of $n$ circles obtained by
+starting in the top row, then repeatedly going from a circle to one of the two circles immediately below it and
+finishing in the bottom row. Here is an example of a Japanese triangle with $n = 6$.
 
          r
         r o
@@ -31,8 +32,8 @@ export const ninjaTrianglePlugin: Plugin = {
      o o o r o
     r o o o o o
 
-    In terms of $n$, find the greatest $k$ such that in each Japanese triangle there is a ninja path containing at
-    least $k$ red circles.
+In terms of $n$, find the greatest $k$ such that in each Japanese triangle there is a ninja path containing at
+least $k$ red circles.
     `,
     icons: [{ label: $localize`🔺️`, order: 2 }],
     filters: [
diff --git a/src/app/service/mod.service.ts b/src/app/service/mod.service.ts
index 40341dbbd..f5c99657e 100644
--- a/src/app/service/mod.service.ts
+++ b/src/app/service/mod.service.ts
@@ -2,8 +2,10 @@ import { DOCUMENT } from '@angular/common';
 import { Inject, Injectable } from '@angular/core';
 import { Title } from '@angular/platform-browser';
 import flatten from 'css-flatten';
+import { marked } from 'marked';
 import { autorun, runInAction } from 'mobx';
 import { of } from 'rxjs';
+import { Plugin } from '../model/plugin';
 import { Store } from '../store/store';
 import { AdminService } from './admin.service';
 import { ConfigService } from './config.service';
@@ -92,6 +94,65 @@ export class ModService {
     this.titleService.setTitle(`${this.config.title} ± ${title}`);
   }
 
+  exportHtml(plugin: Plugin): string {
+    return `<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>${plugin.name || plugin.tag}</title>
+  <style>
+    @media (prefers-color-scheme: dark) {
+      html, body {
+        color-scheme: dark;
+        background-color: #222;
+        color: #c9c9c9;
+      }
+    }
+  </style>
+  <script src="https://cdn.jsdelivr.net/npm/d3@7"></script>
+  <script src="https://cdnjs.cloudflare.com/ajax/libs/handlebars.js/4.7.8/handlebars.min.js"></script>
+  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.css">
+  <script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.js"></script>
+  <script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/contrib/auto-render.min.js"></script>
+  ${plugin.config?.snippet || ''}
+  ${plugin.config?.css || ''}
+  <script id="ui" type="text/x-handlebars-template">
+    ${plugin.config?.ui || ''}
+  </script>
+  <script>
+    window.onload = function() {
+      Handlebars.registerHelper('d3', () => d3);
+      Handlebars.registerHelper('defer', (el, fn) => {
+        if (el.defered) {
+          fn();
+        } else {
+          el.deferred = true;
+          setTimeout(fn, 1);
+        }
+      });
+      var model = {
+        el: document.body
+      };
+      document.getElementById("content").innerHTML = Handlebars.compile(document.getElementById("ui").innerHTML)(model);
+      renderMathInElement(document.body, {
+        delimiters: [
+          {left: '$$', right: '$$', display: true},
+          {left:  '$', right:  '$', display: false},
+        ],
+        throwOnError: false
+      });
+    }
+  </script>
+</head>
+<body>
+  <h1>${plugin.name || plugin.tag}</h1>
+  <p>${marked(plugin.config?.aiInstructions || '')}</p>
+  <div id="content"></div>
+</body>
+</html>
+`;
+  }
+
   private getTheme(id: string, sources: Record<string, string>[]) {
     if (!id) return [];
     return sources.filter(ts => ts[id])
diff --git a/src/app/util/download.ts b/src/app/util/download.ts
index 097a080ad..7060c9127 100644
--- a/src/app/util/download.ts
+++ b/src/app/util/download.ts
@@ -2,7 +2,7 @@ import * as FileSaver from 'file-saver';
 import * as JSZip from 'jszip';
 import { Ext, writeExt } from '../model/ext';
 import { Page } from '../model/page';
-import { writePlugin } from '../model/plugin';
+import { Plugin, writePlugin } from '../model/plugin';
 import { Ref, writeRef } from '../model/ref';
 import { Tag } from '../model/tag';
 import { writeTemplate } from '../model/template';
@@ -46,3 +46,11 @@ export async function downloadSet(ref: Ref[], ext: Ext[], title: string) {
   return zip.generateAsync({ type: 'blob' })
     .then(content => FileSaver.saveAs(content, title + '.zip'));
 }
+
+export function downloadPluginExport(plugin: Plugin, html: string) {
+  const title = plugin.name || plugin.tag.replace('/', '_');
+  const zip = new JSZip();
+  zip.file(title + '.html', html);
+  return zip.generateAsync({ type: 'blob' })
+    .then(content => FileSaver.saveAs(content, title + '.zip'));
+}