URL Query Builder
Network
A clean form for adding, editing, and disabling query parameters one by one, with the resulting URL built live. Keys and values are run through `encodeURIComponent`; you can choose whether to keep spaces as `%20` or fold them to `+` (the form-urlencoded variant). Disabled rows stay in the list but don't appear in the output — handy for stashing alternatives without losing them.
https://api.example.com/search?q=cloudflare%20workers&page=1&sort=relevance
Keys and values are percent-encoded with encodeURIComponent — same rules every well-behaved client uses.
How to use
- Type the base URL. If it already has a `?`, the builder will append the rest with `&`.
- Add key-value rows. Toggle the checkbox to include / exclude a row without deleting it.
- Pick `%20` or `+` for spaces depending on whether the server expects standard URI encoding or form-encoded.
Frequently asked questions
- When do I use `+` for spaces?
- When the server treats the query string as `application/x-www-form-urlencoded` — most older form handlers and CGI scripts do. Modern REST APIs typically accept either, but the safe default for `application/json` POST bodies is `%20`.
- Are duplicate keys allowed?
- Yes — most servers treat repeated keys as an array. Some only keep the last; check the API docs if you're unsure.
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