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JSON tool - JSON Diff

Compare two JSON objects

Paste two JSON payloads and see the differences highlighted with added, removed, and changed values.

JSON Inputs

Paste two JSON objects to compare.

Color legend
+ Added in B− Removed from A~ Modified value Unchanged

Diff result

1 added · 0 removed · 2 modified · 3 unchanged

id1
~name"Alice"→"Alice Smith"
email"alice@example.com"
~role"admin"→"editor"
activetrue
+department"Engineering"

Why this tool exists

Vultio JSON Diff compares two JSON objects and highlights every field that was added, removed, or changed — with path-level detail like user.address.city: "Roma" → "Milano".

It is built for developers who need to quickly spot what changed between two API responses, config snapshots, database records, or test fixtures without setting up a full diff tool.

Common use cases

  • Compare two API responses to find which fields changed between versions.
  • Diff two config files exported as JSON before deploying a change.
  • Verify that a data migration preserved all expected fields and values.
  • Debug frontend state by comparing two snapshots of a Redux store.
  • Review differences between two JSON test fixtures before updating expected outputs.

Example input / output

Detect a changed field

Input

A: {"role":"admin"} · B: {"role":"editor"}

Output

~ role: "admin" → "editor"

Detect an added field

Input

A: {"name":"Alice"} · B: {"name":"Alice","department":"Engineering"}

Output

+ department: "Engineering"

Common errors

JSON A is not valid.

Cause: The first input contains a syntax error — trailing comma, single quotes, or unmatched brackets.

Fix: Validate and format the JSON first using the JSON Formatter, then paste it into the diff tool.

JSON B is not valid.

Cause: The second input contains a syntax error.

Fix: Validate the JSON and check for missing quotes, commas, or brackets.

Related guides

JSON Diff Online: The Complete Guide

How to compare two JSON objects online, understand diff output, and use JSON diff in API debugging and config management.

Standards & references

RFC 6902 — JSON Patch

The IETF standard for describing JSON document changes as a sequence of operations — the formal specification behind what JSON diff represents.

JSON Schema

Use JSON Schema to define the expected structure of your JSON and catch structural changes before they reach a diff tool.

Related tools

JSON Formatter

Format raw JSON to make it easier to inspect.

JSON Minifier

Remove extra spaces from JSON and make it compact.

Type Generator

Convert JSON into TypeScript interfaces or Go structs.

Frequently asked questions

What does JSON Diff online do?

It performs a deep comparison between two JSON objects and highlights every field that was added, removed, or changed. The result is a visual tree with color-coded differences.

What do the colors mean in JSON Diff?

Green means a field was added in JSON B. Red means a field was removed from JSON A. Yellow means a value was changed. Unchanged fields are shown in the default text color.

Does JSON Diff handle nested objects and arrays?

Yes. The diff is recursive: nested objects are compared field by field, and arrays are compared element by element with index-based alignment.

Can I compare JSON arrays, not just objects?

Yes. Top-level arrays are fully supported. Each element is compared at the same index, and elements added or removed are flagged accordingly.

Is my JSON data sent to a server?

No. The diff algorithm runs entirely in your browser. Neither JSON A nor JSON B is transmitted anywhere.