JSON to Query String Converter

Real-world use cases

• Build a request URL from a config object you already have

  Your code holds a search config as a plain object — `{q:"opus 4", tags:["ai","tools"], page:{size:20}}` — and you need the URL to test it by hand in the browser or in curl. Paste the object, pick the repeat array style, flip on the leading `?`, and you get `?q=opus%204&tags=ai&tags=tools&page[size]=20` ready to append to the endpoint. No counting ampersands, no forgetting to escape the space in "opus 4".

• Match the exact array convention a backend expects

  A Rails API wants `tags[]=a&tags[]=b`, a Go service wants `tags=a&tags=b`, and a search API wants `tags=a,b`. Same JSON, three targets. Switch the array format and copy the string that fits the service you are calling, instead of hand-editing brackets and getting it subtly wrong. The live preview shows the result before you paste it into your HTTP client.

• Produce a stable, signable query string

  When you sign a request or use a URL as a cache key, two objects that are logically equal must produce byte-identical strings. Turn on sort and skip-empty: keys come out in lexicographic order and empty values are dropped, so `{b:"",a:"1",c:"2"}` and `{c:"2",a:"1"}` both serialise to `a=1&c=2`. Feed that to your HMAC and the signature is reproducible.

• Clean up an object before putting it in a link

  You are building a share link from form state that has half-filled fields — empty strings, a null, an empty array. Turn on skip-empty and those vanish from the output, so the link carries only the parameters that actually matter instead of a trail of `&ref=&promo=` noise that clutters the URL and your analytics.

Common pitfalls

• Reaching for URLSearchParams with a nested object. `new URLSearchParams({user:{name:'ada'}})` stringifies the object to `[object Object]` rather than nesting it. If your data has any depth, you need bracket-path serialisation, which is exactly what this tool does — copy its output instead of fighting the built-in.

• Choosing the comma array style when you need a round trip. `comma` is compact but lossy: `tags=a,b,c` can't be told apart from a single value that happens to contain commas, so parsing it back can't reliably rebuild the array. If you will ever read the string back into JSON, use repeat or bracket.

• Assuming the result preserves number and boolean types. A query string is text — `{n:42,ok:true}` serialises to `n=42&ok=true`, and when you parse it back you get the strings "42" and "true", not the original types. Cast them on the receiving end; the tool never guesses types, because guessing can corrupt leading zeros and big integers.

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