JSON Minifier

Strip all whitespace from JSON to shrink API payloads and config files, with a byte-for-byte savings report.

JSON ToolsRuns in your browserFree, no sign-up

JSON input

Minified JSON

Output appears here as you type.

Ctrl + Enter to run

About the JSON Minifier

Minifying strips every insignificant space, tab and newline. The saving is real but smaller than it looks over the network, because gzip and brotli already compress repeated whitespace extremely well — a minified response often transmits only a few percent smaller than a formatted one.

Where it genuinely pays is storage that is not compressed: a database column, localStorage, a size-capped API field, or an environment variable. The byte counts shown before and after are the number worth checking before you assume the saving exists.

Frequently asked questions

How much smaller does minified JSON get?

Typically 10–30% for hand-formatted JSON, depending on nesting depth and how much indentation was present. Deeply nested documents save the most because every level adds leading whitespace to every line. The savings figure above the output shows the exact number for your input.

Should I minify JSON if my server already uses gzip?

The marginal gain is small. Gzip and Brotli compress repeated whitespace extremely well, so a minified and a formatted document often land within a few percent of each other on the wire. Minifying is still worth it for data stored uncompressed — database columns, localStorage, embedded config — and for reducing parse time on very large payloads.

Is minified JSON still valid JSON?

Yes. Whitespace between tokens is insignificant in JSON, so a minified document is exactly as valid as a formatted one and every parser accepts it. This tool parses your input before re-serialising it, so invalid JSON is rejected rather than silently compressed.