The JSON diff tool compares two JSON objects and shows exactly what changed — added keys in green, removed keys in red, and modified values in amber. All comparison is done client-side; no data is ever transmitted to a server.
How to Use the JSON Diff Tool
The JSON diff tool helps developers identify changes between two JSON objects — useful for comparing API responses, configuration files, or database records.
Step 1: Paste Your JSON
Paste your original JSON in the left panel (JSON A) and the modified version in the right panel (JSON B). Both must be valid JSON — if parsing fails, the tool shows the exact error location.
Step 2: Click Compare JSON
The tool performs a deep comparison of both objects, recursively checking nested properties. You see a summary: N keys added, N removed, N changed.
Step 3: Read the Diff
The diff output shows each key with its change status: green rows are new keys only in B, red rows are removed keys only in A, amber rows show keys that exist in both but with different values. Each entry shows the full dot-path for nested keys.
Common Use Cases
Comparing API responses between environments (dev vs staging vs production), reviewing configuration changes before deployment, debugging webhook payloads to spot unexpected field additions, and comparing database snapshots to detect schema drift.
Frequently Asked Questions
Is this JSON diff tool free?
Yes, completely free. All comparison logic runs in your browser — no JSON data is ever sent to a server.
Is my JSON data safe?
Completely safe. The diff is computed entirely client-side in JavaScript. Your JSON never leaves your device, is never uploaded, and is never logged. You can use this tool offline once the page loads.
What does the JSON diff show?
The diff shows three types of changes: added keys (in green) that exist in JSON B but not A, removed keys (in red) that exist in A but not B, and changed values (in amber) where the key exists in both but the values differ. Unchanged keys are shown in gray.
Does the diff handle nested objects and arrays?
Yes. The tool recursively compares nested objects, showing the full path (like user.address.city) for deeply nested changes. Arrays are compared element-by-element; element additions, removals, and changes are highlighted separately.
What JSON features are supported?
Standard JSON is fully supported: strings, numbers, booleans, null, objects, and arrays. Comments are not valid JSON and will cause a parse error. If you have JSON5 or JSONC (with comments), strip the comments before comparing.
How do I compare JSON API responses?
Copy the response body from your API client (Postman, Insomnia, browser devtools) and paste into each panel. This is useful for catching API response changes between environments (dev vs prod) or API versions.