Query String Builder
Build encoded query strings from key=value lines.
Building URL query strings manually is error-prone — forgetting to encode special characters or misplacing an ampersand breaks the URL. This builder lets you add key-value pairs visually, handles encoding automatically, and outputs a correctly formatted query string ready to append to any URL.
Your result will appear here...
How to Build a Query String
- Add key-value pairs — enter parameter names and their values.
- Configure encoding — special characters are automatically URL-encoded.
- Copy the query string — the tool generates a properly formatted query string ready to append to any URL.
Frequently Asked Questions
What is a URL query string? ▼
A query string is the part of a URL after the question mark (?). It contains key-value pairs separated by ampersands (&). For example: ?page=2&sort=name&order=asc. Query strings pass parameters to web pages and APIs without changing the URL path.
Why do query string values need encoding? ▼
Some characters have special meaning in URLs (like &, =, ?, #, spaces). URL encoding (percent-encoding) replaces these with safe representations: space becomes %20 or +, & becomes %26. Without encoding, browsers and servers misinterpret the parameters.
What is the maximum length of a query string? ▼
There is no official limit in the HTTP specification, but browsers enforce practical limits. Most browsers support URLs up to 2,083 characters (Internet Explorer's historical limit). For large data, use POST requests instead of query strings.
Can query strings contain arrays? ▼
Yes, though the syntax varies. Common conventions: repeated keys (color=red&color=blue), bracket notation (color[]=red&color[]=blue), or comma-separated values (color=red,blue). The server framework determines which format it expects.
Are query strings case-sensitive? ▼
The parameter names and values are case-sensitive in most server-side implementations. However, this depends on the application. URLs paths may be case-insensitive on some servers (Windows/IIS) but case-sensitive on others (Linux/Apache).
Is my data stored? ▼
No. All processing happens in your browser. No data is sent to any server.