JSON Diff Checker

JSON Diff Checker is a developer tool that semantically compares two JSON objects and highlights every difference with clear visual feedback. Unlike plain text diff, it understands JSON structure — detecting missing properties, type mismatches, value changes, and array modifications at every nesting level. Everything runs 100% in your browser; your data never leaves your machine.

1. 1.Paste your original JSON in the left panel and the modified JSON in the right panel.
2. 2.Click Compare or let auto-compare detect changes as you type.
3. 3.Review the side-by-side view with color-coded highlights: green for added, red for removed, yellow for modified values.
4. 4.Use the navigation arrows or the difference list to jump between changes.
5. 5.Filter differences by type using the checkboxes in the summary bar.
6. 6.Click Copy Result to export a text summary of all differences.

• •Semantic diff — powered by jsondiffpatch for deep structural comparison.
• •Categorized differences — missing properties, type mismatches, value changes, added keys.
• •Side-by-side view with synchronized scrolling and line-level highlighting.
• •Diff navigation — step through differences one by one with prev/next controls.
• •Diff list panel — clickable list of all differences with path and details.
• •Filter system — toggle visibility by difference category.
• •Export — download the diff as HTML or plain text.
• •Session persistence — your inputs are saved automatically via IndexedDB.
• •100% client-side — your data never leaves the browser.

• •Comparing API responses before and after code changes.
• •Verifying configuration file updates (package.json, tsconfig, etc.).
• •Debugging serialization differences between environments.
• •Code review — checking expected vs actual JSON output.
• •Database migration validation — comparing exported records.
• •QA testing — comparing fixture data across test runs.