JSON Diff Checker
Compare two JSON documents as formatted text or a collapsible diff tree
Use JSON Diff Checker free in your browser. Free online JSON diff checker. Compare two JSON documents with red and green line highlights, normalized formatting, sort-keys support, and a collapsible tree diff view — no signup.
What you can do with JSON Diff Checker
JSON Diff Checker on OnliKit is a free browser tool for everyday work — compare two json documents as formatted text or a collapsible diff tree. Use it when you need a quick result without installing software or creating an account.
- Paste two JSON documents and compare them instantly in the browser.
- View differences as a formatted line diff with red removed lines and green added lines.
- Switch to a collapsible tree diff to inspect changed keys and nested structures.
- Sort keys before comparison to reduce noise from key ordering differences.
- Copy or download the diff output and swap left and right inputs in one click.
- All parsing and comparison happen locally on your device for privacy.
Why use JSON Diff Checker?
JSON Diff Checker is useful when API responses, config files, or fixture payloads change and you want to see exactly what moved. It normalizes valid JSON before comparison so formatting differences do not hide the real changes.
The tree view makes nested objects and arrays easier to inspect than a plain text diff alone. Expand only the branches that changed and quickly spot added, removed, or updated keys.
How to use JSON Diff Checker
- 01Paste the first JSON document into JSON A and the second into JSON B.
- 02Optionally enable Sort keys to normalize object ordering.
- 03Review JSON diff for line changes or switch to Tree diff for nested keys.
- 04Copy or download the diff when you are done.
Frequently asked questions
Does JSON diff upload my data?
No. JSON parsing, formatting, and diffing all happen in your browser. OnliKit does not upload your JSON for this tool.
What is the difference between JSON diff and tree diff?
JSON diff shows line-by-line changes in formatted JSON text. Tree diff shows the same changes as a collapsible object tree so nested keys are easier to inspect.
Why would I sort keys before comparing?
Sorting keys removes noise caused only by object key order, which helps you focus on actual value and structure changes.
Can I compare invalid JSON?
The tool requires valid JSON for comparison. If either side is invalid, it reports the parse error so you can fix it first.
Related tools
After you finish with JSON Diff Checker, try these related OnliKit tools — or browse all tools.
- JSON FormatterBeautify, validate, query, and repair JSON in the browser
- JSON ParserParse, format, validate, and inspect JSON in a clean workspace
- JSON ↔ YAML / TOMLConvert between JSON, YAML, and TOML in one workspace
- Diff CheckerCompare two text blocks with inline red and green highlights
Also see more data tools.