DEVELOPER / THE EVERYDAY TOOLKIT
Query String Parser.
Inspect URL query parameters, including repeated keys. This is a free utility from my portfolio toolkit, with local browser processing and no account required.
Repeated keys stay grouped as arrays. Values use URLSearchParams decoding, including + as a space. Nothing is fetched from the URL.
SIMPLE BY DESIGN
How to use Query String Parser
- Paste an absolute URL or a query string such as ?page=2&tag=react&tag=css.
- Generate the result to see each decoded key and every value associated with it.
- Copy the JSON or download it for a reproducible debugging example.
Understand what a URL is actually passing.
Query parameters often control filters, pagination and campaign attribution. This parser separates keys from decoded values and keeps repeated keys in arrays, so tag=react&tag=css does not silently lose a selection. Paste a complete HTTP URL or just the query portion. The output is an inspection aid: it does not fetch the destination, validate an API contract or determine whether an application trusts the parameters.
A FEW THINGS TO KNOW
A little more clarity.
Will duplicate keys overwrite earlier values?
No. Each key has a values array, preserving every occurrence in the original parameter order.
Is my input sent to a server?
No. This utility processes your input in your browser. URLs you paste are treated as data; the tool does not fetch them. Be careful with clipboard history on shared devices.
FROM THE JOURNAL
Build and Read Query Strings with URLSearchParams
Handle repeated parameters, encoding and filter state with an explicit query-string contract.