Query String Builder

Build a URL query string from a simple JSON object.

Build a query string with repeated values preserved
  1. Enter one key=value pair per line or switch to a JSON object.
  2. Optionally add a base URL and choose how spaces are encoded.
  3. Review the complete URL or query string before using it.
Enter a value to begin.

How to use the Query String Builder

What does the Query String Builder do?

Build a URL query string from a simple JSON object; It applies this page-specific rule: each key and value is encoded separately.

Which inputs does this tool use?

To build a url query string from a simple json object, enter Parameter data, Input style, Optional base URL, Encode spaces as; keep every value in the same example; where available, choose between One key=value pair per line, JSON object, + for form-style queries, %20 to match the required format; select Build query string when the values are ready; Start with a familiar case covered by this rule - Repeated keys are preserved, which is important for filters such as tag=tools&tag=browser - so the expected result can confirm the settings.

How should the tool result be read?

For a result intended to build a url query string from a simple json object, repeated keys are preserved, which is important for filters such as tag=tools&tag=browser; read encode spaces as together with the original parameter data rather than as an isolated answer, and confirm that its units or structure match the intended use.

Can the same parameter appear more than once?

When the goal is to build a url query string from a simple json object, yes.

What if a value contains an equals sign?

When using the page to build a url query string from a simple json object, only the first equals sign separates the key; later equals signs remain in the value and are encoded.

Limits and accuracy

When using this tool to build a url query string from a simple json object, a plus sign is the common form-style encoding for a space; check the result in its intended destination before relying on it for important work; keep parameter data until the output has been checked in its intended destination.

How parameter encoding works

Each key and value is encoded separately. Reserved punctuation inside a value is escaped so an ampersand in text cannot accidentally create another parameter.

Repeated keys are preserved, which is important for filters such as tag=tools&tag=browser. JSON arrays also become repeated keys.

A plus sign is the common form-style encoding for a space. Select %20 when the destination expects URI-style space encoding.

Frequently asked questions

Can the same parameter appear more than once?

Yes. Add multiple key=value lines or use a JSON array.

What if a value contains an equals sign?

Only the first equals sign separates the key; later equals signs remain in the value and are encoded.

Will an existing query on the base URL be preserved?

Yes. New parameters are appended with an ampersand.