JSON Viewer

What parsing can change

The formatted copy is what a JavaScript parser understood, which is not always byte for byte what the file says. Integers beyond 9,007,199,254,740,991, such as 64-bit IDs from some APIs, are rounded to the nearest representable number. If a key appears twice in one object, only the last value survives. When exact values matter, compare the output with the original in JSON diff before replacing anything.

JSON Lines is a different format

Logs and data exports often use JSON Lines (.jsonl or .ndjson): one complete JSON value per line, with no enclosing array. A whole-file parser reports an error at the start of the second line. Open one line at a time, or turn the file into a single document by adding commas between lines and wrapping everything in [ and ].

How to use it

1. Choose a JSON file up to 2 MB.
2. Review its type and entry count.
3. Copy or download the formatted JSON.

Privacy & limitations

The file is never uploaded. Syntax validation does not verify an application schema.