Query String Builder
Build URL query strings from key-value pairs or parse existing query strings into editable parameters.
Features
- ✓Build query strings from key-value pairs visually
- ✓Parse existing URLs or query strings into editable rows
- ✓Add, remove, and reorder parameters easily
- ✓Automatically encodes special characters
- ✓Combine with a base URL for a complete link
- ✓Copy the generated URL with one click
How to Use
- 1Optionally enter a base URL (e.g. https://api.example.com/search)
- 2Add key-value pairs using the parameter rows
- 3Click "+ Add Parameter" to add more rows
- 4The generated URL updates in real time
- 5Or paste an existing URL and click "Parse URL" to import its parameters
Examples
Input
Base: https://api.example.com/search | q=hello world, lang=en, page=2
Output
https://api.example.com/search?q=hello+world&lang=en&page=2
Input
Base: https://example.com/landing | utm_source=google, utm_medium=cpc, utm_campaign=spring
Output
https://example.com/landing?utm_source=google&utm_medium=cpc&utm_campaign=spring
What Is a Query String?
A query string is the part of a URL that comes after the question mark (?). It contains key-value pairs separated by ampersands (&), like ?name=John&age=30. Query strings are used to pass data to web servers — search queries, filters, pagination, tracking codes, and API parameters all use this format.
This tool lets you build query strings visually instead of typing them manually. Add key-value pairs using the form, enter a base URL, and the tool generates the complete URL with properly encoded parameters. Special characters like spaces, ampersands, and equals signs are automatically encoded so the URL works correctly.
You can also work in reverse — paste an existing URL and the tool will parse its query parameters into editable rows. This is useful when you need to modify a complex URL, add new parameters, or understand what an existing link is passing to the server.
URL encoding (also called percent-encoding) is applied automatically. A space becomes +, an ampersand becomes %26, and other special characters are converted to their percent-encoded equivalents. This ensures the generated URL is valid and safe to use in browsers, API calls, and redirects.
Everything runs in your browser. Your URLs and parameters are never sent to a server, making this tool safe for building API calls with authentication tokens, internal URLs, and sensitive query parameters.