Bookmarklet Maker

A bookmarklet is a browser bookmark that runs JavaScript on the page you are viewing. Paste your JavaScript below, generate the javascript: URL, then drag the generated link to your bookmarks bar or copy it into a new bookmark.

How to use this tool

Write or paste JavaScript. Leave off the opening javascript: unless you are editing an existing bookmarklet.
Keep the IIFE option enabled unless your code already wraps itself. This keeps variables out of the page's global scope.
Copy the generated URL or drag the generated link to your bookmarks bar.
Open a page, then click the bookmarklet to run it on that page.

Step 1

Write the JavaScript

Bookmark name JavaScript code

const banner = document.createElement('div');
banner.textContent = 'Bookmarklet ran on ' + location.hostname;
Object.assign(banner.style, {
  position: 'fixed',
  top: '16px',
  left: '16px',
  zIndex: '2147483647',
  background: '#4338ca',
  color: 'white',
  padding: '10px 14px',
  borderRadius: '6px',
  font: '14px sans-serif',
});
document.body.appendChild(banner);
setTimeout(() => banner.remove(), 3000);

Wrap in an IIFE End with void 0 Compact whitespace

Step 2

Save the bookmarklet

0 chars

Generated bookmark URL

Ready.

Drag this link to your bookmarks bar:

My Bookmarklet

Step 3

Test in the sandbox

The local sandbox runs your code in an iframe test page. You can also enter a URL to see whether a page can be embedded.

If a URL test fails, save the bookmarklet and test it directly on that page. Remote sites often block iframe embeds or cross-origin scripting, which is normal browser security.

Sandbox URL

Local sandbox ready.

Console output

Console output will appear here.

Step 4 (Optional)

Use Bookmark Llama when a bookmarklet needs to live in a shared folder, not as a one-off bookmark. Your team keeps using the browser's native bookmarks, and when you update a shared bookmarklet or bookmark, it automatically updates in everyone's browser.

See bookmark sharing

How to use this tool

Write the JavaScript

Save the bookmarklet

Test in the sandbox

Share your bookmarklets with others