Query String Parser

How to use Query String Parser

1. Open Query String Parser — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use Query String Parser?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full developer tools suite, so related query string parser tasks are one click away.

What people use Query String Parser for

• Breaking a long tracking URL into readable parameters to see what is being sent.
• Debugging a redirect or callback URL that is not carrying the values you expect.
• Extracting UTM parameters from a campaign link.

Query String Parser: limits and things worth knowing

• A key can legitimately appear more than once — ?tag=a&tag=b — and different frameworks resolve that differently: some take the first, some the last, some build an array. Seeing the raw repetition is often the point.
• A plus sign in a query string means a space, a legacy of form encoding. %2B is a literal plus, and confusing the two corrupts signatures and base64 values.
• Values are percent-decoded on parse, so a parameter containing its own & or = shows correctly rather than splitting the string.
• Query strings routinely carry session tokens and personal data, which is a good reason to parse them in your own browser.

Is it private and secure?

Your privacy is built in. Query String Parser runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

Is It Safe to Paste Production Data Into Online Tools? — JWTs, API responses and env files get pasted into online formatters every day. Here's what actually happens to that data and how to check before you paste.