Fastway Tools

JSON Diff

Spotting what changed between two JSON payloads — an API response before and after, two config versions — is hard when formatting or key order differs. This free JSON Diff normalizes both sides (pretty-print + sorted keys) and shows a clear line-by-line comparison, so you see only the real changes, instantly in your browser.

How to use it

  1. Paste the original JSON on the left.
  2. Paste the changed JSON on the right.
  3. Read the highlighted diff — green added, red removed.

Why use this tool

  • Ignores formatting and key-order noise.
  • Clear added/removed line highlighting and counts.
  • Runs in your browser — private and free.

FAQ

How does it compare the two?

Both inputs are pretty-printed with sorted keys, then compared line by line — so reformatting or key order alone never shows as a difference.

What do the colors mean?

Green lines were added in the changed JSON; red lines were removed from the original.

Is my data uploaded?

No. The comparison runs entirely in your browser.