JSON Formatter

What it does

Pretty-prints JSON with the indent you choose (2 spaces, 4 spaces, or tabs). It changes whitespace and nothing else.

Why it is different

Most online formatters parse your JSON into a JavaScript value and re-serialize it. That quietly corrupts real payloads: an ID past 2⁵³ (Snowflake, Twitter, Stripe) becomes a different number, 1.0 collapses to 1, 1e3 becomes 1000, -0 is lost, integer-like keys get reordered, and duplicate keys are silently dropped. This formatter works on the source text directly, so every one of those is preserved exactly.

When to use it

Reading an API response, a config file, or a log line that arrived as one dense string and you want it laid out without risking a single changed character.

Privacy

It runs entirely in your browser. What you paste is never uploaded, and the page works offline after the first load.