Online Query String Parser and Builder
Parse query parameters into editable rows, preserve repeated keys, and build a correctly encoded query string without sending data anywhere. It solves the common problem of debugging filters, pagination parameters, and repeated keys inside long URLs.
What is a query string parser?
A query string is the key-value portion after a URL's question mark. It carries filters, pagination, search terms, feature flags, and other small pieces of state between a browser and a web application.
How to use this parser and builder
Paste a query string and click Parse query string. Edit any row, add new pairs, or remove values. The generated string updates as you work and uses standard URL encoding.
Repeated parameters and encoding
Repeated keys are meaningful in many APIs, so this tool keeps each occurrence as its own row. Spaces and punctuation are encoded by the browser URLSearchParams implementation.
How to use Query String Parser for related tasks
Parse the query string, edit each key-value pair, and use the encoded output when building a request or shareable link.
Related tools: URL Parser, REST API Tester.
Frequently asked questions
Can this parse a query string without a full URL?
Yes. Paste a string beginning with ? or a bare query such as page=2&sort=name.
Are duplicate keys preserved?
Yes. Repeated keys are shown as separate rows and remain repeated when the query string is rebuilt.
How is URL encoding handled?
The browser URLSearchParams API encodes spaces, symbols, and non-ASCII characters when building the result.
How do I encode query parameters correctly?
Edit the key-value rows and let the builder apply URL encoding, including safe handling for spaces, symbols, and repeated parameters.