URL Query Parser -- Parse & Rebuild Parameters

Parse URL Query Parameters

URL Query Parser extracts and displays all components of a URL, including query parameters, protocol, host, path, and fragment. Edit parameter values and rebuild the URL with live updates.

How URL Query Strings Work

A URL query string is the portion of a URL that comes after the question mark (?). It contains key-value pairs used to pass data to web servers or applications.

Structure

protocol://host:port/path?key1=value1&key2=value2#fragment

Query Parameter Rules

• Start with ? — The query string begins after the question mark
• Key-value pairs — Format is key=value
• Separated by & — Multiple parameters are joined with ampersands
• URL encoding — Special characters are percent-encoded (space becomes %20, etc.)
• Duplicate keys allowed — Multiple parameters can share the same key name
• Empty values permitted — key= or just key (no equals sign)

Common Use Cases

• Search queries — ?q=javascript&page=2
• Filters — ?category=electronics&price=100-500
• Tracking parameters — ?utm_source=google&utm_medium=cpc
• Pagination — ?page=3&limit=20
• API parameters — ?format=json&api_key=abc123

URL Encoding Reference

Special characters in URLs must be percent-encoded using the format %XX where XX is the hexadecimal representation of the character's ASCII value.

Frequently Asked Questions

What is a URL query string?

A URL query string is the part of a URL after the question mark (?). It contains key-value pairs separated by ampersands (&), used to pass data to web servers or applications. Example: ?name=John&age=30

How do I decode URL-encoded characters?

URL-encoded characters use percent-encoding where special characters are replaced with %XX (hexadecimal). This tool automatically decodes them: %20 becomes space, %2B becomes +, %3D becomes =, etc. The decoded values appear in the rightmost column.

Can I have duplicate keys in query parameters?

Yes. Multiple parameters can share the same key (e.g., ?color=red&color=blue). Many server frameworks interpret these as arrays. This tool shows all duplicate keys and preserves them when rebuilding the URL.

What's the difference between query parameters and fragments?

Query parameters (after ?) are sent to the server with HTTP requests. Fragments (after #) are client-side only and never sent to servers. Fragments are used for page anchors or client-side routing in single-page applications.

How do I build a URL from scratch?

Start with a basic URL (like https://example.com/path), paste it into the tool, then use the Add Parameter button to insert new query parameters. The URL rebuilds automatically as you add or edit parameters.

What characters need URL encoding?

Reserved characters that need encoding include: space, ampersand (&), equals (=), question mark (?), hash (#), percent (%), plus (+), and others. Use encodeURIComponent() in JavaScript or equivalent functions in other languages.

Is it safe to paste URLs with sensitive data?

This tool runs entirely in your browser using JavaScript. Your URLs and parameters are never sent to any server. However, avoid pasting URLs containing passwords, API keys, or tokens into tools you don't trust.

How are empty parameter values handled?

Parameters can have empty values (key=) or no equals sign at all (just key). This tool preserves both formats. Empty values appear as blank cells in the table and are maintained when rebuilding the URL.

Related Tools

• URL Encoder/Decoder — encode and decode URL components
• Base64 Encoder/Decoder — encode data for URL-safe transmission
• JSON Formatter — format and validate JSON API responses
• UTM Link Builder — build tracking URLs with UTM parameters
• User-Agent Parser — parse browser user-agent strings

URL Query Parser FAQ