Developer Tools
Build a URL query string from JSON or key-value lines.
Use this query string builder to create URL query strings from JSON objects or simple key=value lines. It is useful for APIs, testing, redirects, search links, campaign parameters, and quick URL construction without building parameter strings manually.
Use this query string builder to create URL query strings from JSON objects or simple key=value lines. It is useful for APIs, testing, redirects, search links, campaign parameters, and quick URL construction without building parameter strings manually.
Use query string builder when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.
Read step-by-step usage guidance, best practices, and common mistakes.
See common questions and answers about input, output, and tool usage.
Review practical input and output examples before running the tool.
Find similar and supporting tools for adjacent actions and follow-up tasks.
Input
{"q":"hello world","page":2} Output
q=hello%20world&page=2
Builds a query string from JSON key-value data.
Input
utm_source=email utm_campaign=spring
Output
utm_source=email&utm_campaign=spring
Useful when assembling campaign parameters from simple lines.
Fix: Use either a valid JSON object or clean key=value lines.
Fix: Add the domain and path separately if you need a complete URL.
Fix: Review the encoded output carefully if the target system has strict parameter rules.
You can use either a JSON object or simple key=value lines, one per line.
Yes. Arrays become repeated query parameters with the same key.
It is useful when building API request strings, redirects, search links, and campaign URLs.
Yes. It works online in the browser.
Use the builder when you want structured key-value parameters assembled into a full query string. Use the encoder when you only need raw text encoded.