JSON Diff
Compare two JSON files and produce a unified diff over their canonical (key-sorted) pretty form. Reorderings vanish; real changes stand out.
About JSON Diff
JSON Diff compares two JSON files and shows a unified diff over their canonical, key-sorted, pretty-printed form. Because both sides are normalized first, harmless key reorderings disappear and only the real changes show up. It is the tool to grab when a config or API response 'looks different' but a plain text diff is drowning you in noise. Everything runs in your browser.
- Category
- inspect
- Input
- Accepts: application/json or text/plain.
- Output
- Outputs: text/plain (multiple).
- Cost
- Free, runs in your browser
- Memory
- low
Common uses
- Compare two API responses to find exactly which fields changed between calls
- Diff a config file before and after a deploy without false positives from reordered keys
- Review what a tool rewrote in a package.json or settings file
- Spot an unexpected value change in a large JSON export during code review
- Confirm that two JSON files are semantically identical despite different key order
- Track down which nested field broke a downstream consumer
Frequently asked questions
Why use this instead of a plain text diff?
A text diff flags reordered keys and whitespace as changes. JSON Diff canonicalizes both inputs (sorts keys, pretty-prints) so only genuine value or structure changes appear.
What format is the output?
A unified diff in plain text, the same format you would see from a tool like git diff, ready to read or paste into a review.
Do reordered object keys show as changes?
No. Keys are sorted before comparison, so two objects with the same keys in different order compare as equal.
Does my JSON get sent to a server?
No. Both files are parsed and diffed entirely in your browser.
What if one of my files is not valid JSON?
Both inputs must parse as JSON. If one is malformed, the tool cannot canonicalize it and will report the parse problem rather than diff invalid text.
Keywords
- json
- diff
- compare
- changes
- unified
- patch