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Tools / Encoding

Query String Builder

Parse and construct query strings with editable parameter rows, duplicate keys, blank values and fragments entirely in your browser.

Repeated names, parameter order, blank values and #fragments are preserved. Encoding uses URLSearchParams (spaces become +). No URL is opened or fetched.

What is Query String Builder?

Query strings represent key-value pairs after the question mark in a URL. They can include repeated names, empty values, Unicode, and fragments after a hash. This tool reads existing HTTP(S) URLs or relative paths and lets you edit parameters individually, preserving duplicates and their order. It uses standard form-style URLSearchParams encoding, which represents spaces as plus signs. Parsing and building happen locally; this tool never opens or fetches the URL.

How to use this tool

  1. Paste an HTTP(S) URL or relative path and load its query parameters.
  2. Add, edit or remove parameter rows, retaining repeated names and optional empty values.
  3. Build a new URL, then copy or download the result.

Example

https://example.com/search?q=hello+world&tag=one&tag=two#results

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