Compare anything, see exactly what changed
Finding the difference between two versions by eye is slow and error-prone, especially in long documents or deeply nested data. These diff tools compare two inputs and highlight every change, from a single edited word to reordered sections. There is a tool for plain text and files, and structure-aware tools for JSON and XML that ignore meaningless differences such as indentation and key order.
Which diff tool should you use?
| You are comparing | Use | Why |
|---|---|---|
| Documents, code snippets, lists | Diff checker | Line and word-level highlighting, side-by-side or unified view |
| Two files from disk | File diff | Loads files and produces a downloadable patch with context lines |
| API responses, configs in JSON | JSON diff | Compares values by path; ignores key order and formatting |
| XML feeds, SOAP, project files | XML diff | Normalizes formatting and attribute order first |
Reading a diff
- Lines marked with
-(usually red) exist only in the original. - Lines marked with
+(usually green) exist only in the new version. - A removed and an added line at the same place are shown as a changed line, with the differing words highlighted.
- In JSON diff, paths like
$.items[2].pricetell you exactly where a value changed.
Options that reduce noise
Real-world comparisons often suffer from irrelevant differences. Ignore whitespace to hide re-indentation, ignore case for case-insensitive content, and trim trailing spaces that editors add invisibly. Line endings from Windows and Unix are normalized automatically. For data, the JSON and XML tools remove formatting differences entirely by comparing structure.
Typical uses
- Reviewing edits to contracts, policies and articles.
- Finding configuration drift between staging and production.
- Checking what changed in an API response after a release.
- Verifying that a refactoring or format conversion did not change content, for example after running the JSON formatter.
Prepare inputs for cleaner diffs
Differences are easiest to read when both sides are formatted the same way. Run both versions through the XML formatter or a code formatter first, or clean prose with the text formatter, so layout changes do not hide the edits that matter. For sorted lists, sort both sides before comparing to see only real additions and removals.
Privacy
Comparisons run entirely in your browser, so confidential documents and source code are never uploaded. For long texts with many changes, a desktop tool or Git may be faster, but for quick comparisons nothing beats pasting two versions side by side.