Bookmarklet Builder
Turn JavaScript into a bookmarklet URL without running the code.
Copy the URL into a bookmark’s address field. Run it only on pages where you intend to execute the code. A website’s CSP or browser policy may block bookmarklets.
A QUICK WALKTHROUGH
How to use this tool
- Paste raw JavaScript, without the javascript: prefix. Up to 100 KB. The code is wrapped in an IIFE with void so its return value cannot replace the page.
- Generate bookmarklet → Copy URL
- Copy the URL into a bookmark’s address field. Run it only on pages where you intend to execute the code. A website’s CSP or browser policy may block bookmarklets.
Build locally
Nothing is uploaded or saved. Syntax and runtime errors remain your code’s responsibility.
Bookmarklet URL
Paste raw JavaScript, without the javascript: prefix. Up to 100 KB. The code is wrapped in an IIFE with void so its return value cannot replace the page.
JavaScript code
The original code, comments and line breaks are preserved; URL encoding is not minification.
GOOD TO KNOW
Common questions
Generate bookmarklet?
Copy the URL into a bookmark’s address field. Run it only on pages where you intend to execute the code. A website’s CSP or browser policy may block bookmarklets.
JavaScript code?
URL generated. This builder does not validate or execute your code.