JSON Compress

JSON Compress makes JSON smaller by taking out the repetition, and what it writes is still valid JSON. Each key name is written once, arrays of like-shaped objects become columns and rows, a column that never changes is stored once, and repeated strings go into a catalogue. On record-shaped data the result is typically 45 to 75% smaller than minified JSON. It restores byte for byte, with key order and the difference between a null and a missing key kept.

One written specification has six implementations that all write the same bytes: JavaScript, .NET, Python, Go and Rust at 1.0.3, and PHP from the repository. None has a dependency. In a browser it loads from jsDelivr with no build step.

It is not always the right tool. On a small document with little repetition gzip alone does better, and its stats command tells you which case you are in.

Free and open source under the MIT licence. JSON Compress is a Tech Style product.