JSON Compare Tool Online

Compare two JSON objects, arrays, files, or API payloads in the browser and review the exact paths that changed.

Paste your JSON → Get results instantly (no signup)

⚡ Instant resultsNo signupRuns in your browser

Try examples:

→ Compare these JSON inputs and return a report of changed, added, and removed fi...

Output✓

{
  "plan": "pro",
  "features": {
    "aiDraft": true,
    "history": true,
    "apiAccess": true
  },
  "limits": {
    "documents": 100
  }
}

Output✓

1{
2  "changed": [
3    {
4      "kind": "changed",
5      "path": "plan",
6      "before": "starter",
7      "after": "pro"
8    },
9    {
10      "kind": "changed",
11      "path": "features.aiDraft",
12      "before": false,
13      "after": true
14    },
15    {
16      "kind": "changed",
17      "path": "limits.documents",
18      "before": 10,
19      "after": 100
20    }
21  ],
22  "added": [
23    {
24      "kind": "added",
25      "path": "features.apiAccess",
26      "value": true
27    }
28  ],
29  "removed": [
30    {
31      "kind": "removed",
32      "path": "features.legacyExport",
33      "value": true
34    }
35  ]
36}

Love the result?

Use this exact pipeline in your app, backend, or LLM workflow.

No setup needed. Works with curl, Node, Python.

Uses example data. For edited input, copy from the playground.

Read integration guide

Works with:

JSON objects and arrays
Config snapshots
API samples
Before-and-after payloads

Example: input → output

Inputs / Output

Output

JSON compare tool online

Use this JSON compare tool when you have two structured payloads and need a quick answer to what changed. The input can be a pair of JSON objects, arrays, API samples, fixture exports, or copied file contents. The comparison engine reads the data as JSON first, then reports changed paths instead of raw line edits.

That distinction is important for everyday debugging. A pretty-printer can make a text diff look huge even when the payload means the same thing. A structured compare view keeps the review centered on the fields an application consumes: added keys, removed keys, and values that changed under a stable path.

When to use JSON compare

JSON compare is useful when a teammate asks whether two payloads are equivalent, when a test fixture changed after a script ran, or when a vendor response looks almost identical but a nested field is breaking code. It also helps when you need to explain a change to someone who does not want to read a full raw diff.

Common examples include comparing customer records before and after cleanup, checking feature-flag exports between environments, reviewing generated JSON from an LLM prompt change, and confirming that a migration kept required values intact.

For the canonical broader page, see the JSON diff tool.

How to compare two JSON objects

Paste the baseline payload into the old side and the changed payload into the new side. Run the comparison, then scan the report for added, removed, and changed entries. If the result is too noisy, clean both inputs with Clean JSON, validate them with JSON Validator, or flatten deep structures with Flatten JSON.

The most reliable compare workflow starts with equivalent preparation on both sides. Do not normalize only one input unless the point of the review is to verify that normalization itself. If array order is not meaningful in your domain, sort or normalize arrays before comparing so the report does not treat reordered items as unrelated changes.

JSON compare examples

A product object might change from {"plan":"starter","active":true} to {"plan":"pro","active":true}. A structured comparison should call out only the plan value change. In larger payloads, the same principle applies to nested paths such as account.limits.documents, features.auditLog, or items.0.price.

That makes the report useful in bug tickets, release notes, QA handoff, and integration reviews. Instead of saying "something changed in this JSON," you can point to the exact field and value.

JSON Diff Tool - canonical structured diff workflow for added, removed, and changed fields.
Compare JSON files online - file-focused comparison for fixtures, configs, and exports.
JSON difference checker - changed-field reporting for debugging payload drift.
JSON diff online - browser-based no-upload JSON comparison.
API JSON diff - compare endpoint, webhook, and SDK response changes.
Compare JSON objects - object-level field comparison.
JSON file diff - saved-file and fixture diff workflow.
Find JSON changes - added, removed, and modified field detection.
Compare API JSON responses - endpoint and webhook response comparison.

JSON Validator - validate both inputs before comparing.
JSON Formatter - clean and format JSON before diffing.
Clean JSON - remove formatting and empty-field noise before diffing.
Flatten JSON - convert deep objects into readable paths.
Normalize JSON - align inconsistent field names before comparison.
JSON to CSV - export reviewed JSON or flattened data to a spreadsheet.

Related tools

Related comparisons

JSON Diff / Change Report

v1.0.0

Compare

objectarray

Description

JSON Diff / Change Report

Compare two JSON inputs and output a structured report or focused diff subset. Accepts a primary input (the new JSON) and secondary input (the old JSON), then shows what changed, was added, or was removed between them.

How It Works

This utility requires two inputs — primary (the "new" version) and secondary (the "old" version). It performs a deep comparison and outputs results based on the selected mode.

Diff Modes

Report

Return a structured report with changed, added, and removed arrays. Entries include dot paths, kind, and either before/after values or the added/removed value.

Changed Only

Return the subset of the new JSON that differs from the old JSON. Modified and added fields are included; removed fields are excluded because they do not exist in the new JSON.

Added Only

Show only fields that exist in the primary input but not in the secondary. Useful for detecting new additions.

Removed Only

Show only fields that exist in the secondary input but not in the primary. Useful for detecting deletions.

Full Annotated

Show all fields with _diff_ markers indicating their status: "unchanged", "changed", "added", or "removed". Provides a complete picture of all differences.

Configuration

Field	Type	Default	Description
Diff Mode	enum	`report`	`report`, `changed-only`, `added-only`, `removed-only`, or `full-annotated`

Use Cases

Version Comparison

Config changes: Compare two versions of a configuration file to see what changed
API responses: Diff API responses before and after a deployment
Schema evolution: Identify added or removed fields between schema versions

Data Validation

Migration verification: Compare source and target data after migration
Sync detection: Find out-of-sync records between two data sources
Audit trail: Track exactly which fields were modified in an update

Debugging

State inspection: Compare application state before and after an action
Response diffing: Compare expected vs. actual API responses
Regression detection: Identify unexpected changes in output data

Configuration

Name	Type	Default	Description
Diff Mode	`enum`	`report`	report: return changed, added, and removed entries with paths. changed-only: show the new JSON subset with modified and added values. added-only: show only new keys. removed-only: show only deleted keys. full-annotated: show all with _diff markers. `report` `changed-only` `added-only` `removed-only` `full-annotated`

Examples

AI Prompt

Compare these JSON inputs and return a report of changed, added, and removed fields.

Output✓

{
  "plan": "pro",
  "features": {
    "aiDraft": true,
    "history": true,
    "apiAccess": true
  },
  "limits": {
    "documents": 100
  }
}

Output✓

1{
2  "changed": [
3    {
4      "kind": "changed",
5      "path": "plan",
6      "before": "starter",
7      "after": "pro"
8    },
9    {
10      "kind": "changed",
11      "path": "features.aiDraft",
12      "before": false,
13      "after": true
14    },
15    {
16      "kind": "changed",
17      "path": "limits.documents",
18      "before": 10,
19      "after": 100
20    }
21  ],
22  "added": [
23    {
24      "kind": "added",
25      "path": "features.apiAccess",
26      "value": true
27    }
28  ],
29  "removed": [
30    {
31      "kind": "removed",
32      "path": "features.legacyExport",
33      "value": true
34    }
35  ]
36}

Config

Diff Mode

report

API Usage

POST /api/v1/utilities/compare.json-diff

Example:

curl -X POST https://your-domain.com/api/v1/utilities/compare.json-diff \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"inputs":{"primary":{"plan":"pro","features":{"aiDraft":true,"history":true,"apiAccess":true},"limits":{"documents":100}},"secondary":{"plan":"starter","features":{"aiDraft":false,"history":true,"legacyExport":true},"limits":{"documents":10}}},"config":{"mode":"report"}}'

Response

1{
2  "changed": [
3    {
4      "kind": "changed",
5      "path": "plan",
6      "before": "starter",
7      "after": "pro"
8    },
9    {
10      "kind": "changed",
11      "path": "features.aiDraft",
12      "before": false,
13      "after": true
14    },
15    {
16      "kind": "changed",
17      "path": "limits.documents",
18      "before": 10,
19      "after": 100
20    }
21  ],
22  "added": [
23    {
24      "kind": "added",
25      "path": "features.apiAccess",
26      "value": true
27    }
28  ],
29  "removed": [
30    {
31      "kind": "removed",
32      "path": "features.legacyExport",
33      "value": true
34    }
35  ]
36}

Love the result?

Example: input → output

JSON compare tool online

When to use JSON compare

How to compare two JSON objects

JSON compare examples

Related conversions

Related tools

Related tools

Related comparisons

Read more on the blog

JSON Diff / Change Report

Description

JSON Diff / Change Report

How It Works

Diff Modes

Report

Changed Only

Added Only

Removed Only

Full Annotated

Configuration

Use Cases

Version Comparison

Data Validation

Debugging

Configuration

Examples

API Usage

Related Tools

JSON Validator

JSON Formatter

JSON to CSV

Clean Values

Flatten / Nest