Free browser utility
Query String Parser and Builder
Repeated parameter names are represented as arrays so no values are silently lost.
✓ Local processing✓ No registration✓ No file upload
Loading tool…
Before
?tag=php&tag=javascript&page=2
→
After
{"tag":["php","javascript"],"page":"2"}How to use Query String Parser and Builder
- Paste text or select local files in the tool area.
- Choose any options that match the source data.
- Run the conversion or repair and review the preview.
- Copy the result or download the generated file.
Privacy and local processing
This project performs processing, document generation or calculations in your browser. The page does not include an upload endpoint, analytics script or remote processing API call. Avoid pasting sensitive data into websites you do not control.
Frequently asked questions
Can I paste a complete URL?
Yes. The parser extracts the portion after the question mark.
How are repeated keys handled?
Repeated keys become arrays in parsed JSON and are repeated again when rebuilding the query string.