Query String Builder
Add key/value pairs and an optional base URL to build a properly encoded query string, or paste an existing URL to parse its parameters back into editable rows. Runs entirely in your browser.
Developer Tools Runs entirely in your browser
All processing happens on your device and your data is never sent to any server.
Parameters (Key/Value)
Resulting query string
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What this tool does
Builds a query string from key/value pairs you add, or parses an existing one into an editable table, with an optional base URL.
When to use it
- Building a campaign link with several parameters.
- Changing one parameter in a long URL without editing the text by hand.
- Testing an endpoint with different parameters.
- Building a URL whose parameter values contain spaces or characters needing encoding.
How to use it
- Paste an existing query string and click "Parse" if you are starting from one.
- Enter a "Base URL (optional)" if you want a complete link.
- Add "Parameters (Key/Value)" one at a time with "Add parameter", and delete any you do not want.
- Copy the "Resulting query string".
A practical example
Input
Base URL https://example.com/page with parameters a=1 and b=2.
Output
https://example.com/page?a=1&b=2, ready to copy.
Limitations
- The base URL is optional; without one you get the query string alone.
- Values are encoded automatically where needed, so do not pre-encode them or they will be encoded twice.
- Parameters with an empty value are included as they are, which is correct because some systems distinguish an empty parameter from an absent one.
Privacy and processing
All processing happens on your device and your data is never sent to any server.
Technical notes
- The output follows standard URL encoding rules, so it works in any browser or server.