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Free JSON Diff Viewer
for structured JSON comparison.

Compare two JSON documents instantly with this free online JSON diff viewer. No accounts. No uploads. No telemetry.

Original JSON

Updated JSON

Diff summary

Found 6 differences.

Changed

  • active

    before: true

    after: false

  • settings.theme

    before: "dark"

    after: "light"

  • user.name

    before: "Alice"

    after: "Alice Johnson"

Added

  • lastLogin

    "2026-03-12T09:00:00Z"

  • roles.2

    "billing"

Removed

  • user.address.zip

    "H2X"

Supported

  • Nested JSON objects
  • Arrays and indexed array paths
  • Added, removed and changed value detection
  • Order-insensitive comparison for object keys
  • Structural comparison instead of raw text comparison

Automatically handled

  • JSON validation on both sides in real time
  • Pretty rendering of changed values
  • Differences on deeply nested paths like user.address.city
  • Root-level primitive comparison

Not supported yet

  • Side-by-side colored inline diff blocks
  • Ignored-path rules
  • Sorting arrays before comparison
  • Patch export
  • JSON file uploads

Free online JSON diff viewer

This tool works as a JSON diff viewer, a JSON compare tool, and a quick way to detect structural differences between two JSON documents.

It highlights changed values, added keys, removed keys, and nested path differences so you can quickly inspect what changed between two payloads.

Developers often compare JSON from API responses, configuration files, webhook payloads, exported data, and before-and-after application state.

Unlike plain text diff tools, this viewer parses the JSON first, so formatting changes alone do not create noise.

Example

{
  "status": "draft",
  "count": 2
}

Paste one version on the left and another on the right to instantly see which paths changed and what the before and after values are.

Compare two JSON documents online

Use this JSON comparison tool to quickly compare two JSON objects, API payloads, or configuration files directly in your browser.

Common use cases

  • Compare API responses between environments
  • Inspect webhook payload changes
  • Review configuration differences between JSON files
  • Debug before-and-after transformations in apps and scripts

How it works

The viewer parses both JSON inputs, recursively walks through objects and arrays, and compares every path in the structure.

When a key or array index exists only on one side, it is marked as added or removed. When the same path exists on both sides but the values differ, it is marked as changed.

Everything runs locally in the browser, so your JSON never leaves your machine.

Why use a JSON diff viewer instead of a text diff tool?

A plain text diff can show lots of noise when JSON formatting changes, indentation changes, or object keys move around.

A structured JSON diff viewer compares the parsed data itself, which makes it easier to spot meaningful changes in values, keys, arrays, and nested objects.

FAQ

What is a JSON diff viewer?

A JSON diff viewer compares two JSON documents and shows what was added, removed, or changed.

Does this compare JSON structurally?

Yes. The tool parses the JSON first and compares the structure and values, not just the raw text.

Is this JSON diff tool safe?

Yes. Everything runs in your browser and your JSON is not uploaded.

More developer tools

DevWrench provides a growing collection of browser-based developer tools including JSON utilities, converters, encoders, and debugging helpers. Browse them below.

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