Turn key and value lines or a JSON object into a correctly escaped query string, with repeated keys for array values and optional RFC 3986 strict escaping.
Show calculation steps
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How to use the Query String Builder
- Enter your parameters as "key = value" lines, one per line, or switch the input format to JSON.
- Repeat a key on several lines – or use a JSON array – to produce repeated parameters.
- Choose whether spaces become plus signs and whether to apply strict RFC 3986 escaping.
- Click "Build query string" and append the result to your URL.
Frequently asked questions
How do I create an array parameter?
Repeat the key. Writing "tag = a" and "tag = b" on separate lines produces "tag=a&tag=b", which is the form most APIs expect. In JSON mode, give the key an array value and the same output is produced.
Are my keys and values escaped for me?
Yes, both. Every key and every value is percent-encoded independently, so an ampersand or equals sign inside a value cannot break the structure of the query string.
Should I include the leading question mark?
Include it when you are appending the result to a URL that has no query string yet. Leave it off when you are joining onto an existing query with an ampersand. The option controls this.
