URL Builder

Build URLs from a base URL, query parameters, and a hash fragment. All processing is done locally in your browser.

The URL Builder requires JavaScript. Enable JavaScript in your browser to use this page.

/* When JavaScript is unavailable there is no client-only island to hydrate, so hide the decorative skeleton and collapse the reserved min-height. The route-level <RequiresJavaScript> notice becomes the sole fallback UI instead of stacking a fake tool shell underneath it. */ .client-only-island-shell { min-height: 0 !important; } .client-only-island-shell__placeholder { display: none; }

What this URL builder does

Start with a base URL, add or remove query parameters, set a hash fragment, and copy the finished result once it looks right. The tool rebuilds the URL live with the browser's WHATWG URL API, so encoding and query-string assembly match what modern browsers do.

If you need to inspect an existing URL first, use the dedicated URL Parser page to break it into parts and review decoded query parameter values.

URL builder examples

Assemble an API request URL by adding query parameters one at a time and checking the final encoded result.
Paste a full URL into Base URL, then tab out to split its query string and fragment into editable fields.
Build redirect or callback URLs with repeated keys like ?tag=a&tag=b.
Confirm how spaces and special characters are encoded before you paste a URL into browser or API tooling.

How to use the URL builder

Enter a full absolute URL into Base URL. If you paste a URL that already contains a query string or hash, the tool keeps the live result correct immediately.
Add query parameter rows as needed, then edit each key and value in place.
Set the hash fragment in the dedicated field if you want the result to end with #section or a similar anchor.
Copy the final highlighted result once the URL matches the request you want to send or share.

URL builder FAQ

Do I need to include the protocol?

Yes. The builder requires an absolute URL like https://example.com/path. Inputs like example.com/path are treated as invalid until you add a protocol.

Can I repeat the same key more than once?

Yes. The builder appends every non-empty key in the order shown, so repeated keys like tag or filter stay intact in the output.

What happens if I paste a full URL into Base URL?

The live result updates immediately. When you leave the field, the builder moves any query params into editable rows and copies the fragment into the dedicated hash input so the editing surface stays organized.

How is my URL processed?

All URL building happens entirely in your browser with the WHATWG URL API. Nothing is uploaded to a server.

Privacy

All URL building happens entirely in your browser. The base URL, query parameters, and hash fragment never leave your device.