Find JSON Differences Online

Paste two JSON payloads and find differences by path, including added keys, removed keys, and changed values.

Paste your JSON → Get results instantly (no signup)

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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:

Changed field reports
Nested JSON paths
Release QA
Debugging payload drift

Example: input → output

Inputs / Output

Output

JSON difference checker

A JSON difference checker helps you find the exact data-level changes between two JSON inputs. It is built for moments where "these payloads are different" is not enough. You need to know which field changed, whether a key was removed, and whether a new nested value appeared.

This page focuses on changed-field reporting. Paste two payloads, run the checker, and inspect the output by path. The report is easier to review than a raw line diff because JSON is parsed as data before the comparison happens.

For the main comparison page and shared engine, open the structured JSON diff.

What counts as a JSON difference?

The most common difference types are added fields, removed fields, and changed values. An added field means the new payload contains a path that did not exist in the baseline. A removed field means the baseline had a path that the new payload no longer includes. A changed value means both payloads contain the same path but the value is different.

Nested JSON makes those categories more valuable. If a deeply nested response changes from "status":"trial" to "status":"active", a structured checker can identify the path directly instead of forcing the reviewer to search through the whole document.

Difference checking for debugging

Use this workflow when an API changed unexpectedly, a config stopped matching production, a test fixture drifted, or an exported file no longer matches a known-good snapshot. It is especially helpful for regression checks because the report separates shape changes from formatting changes.

Before running the checker, make both sides valid JSON with JSON Validator. If unwanted nulls or blank strings create noise, clean both payloads with Clean JSON. If you only care about selected paths, use Extract Fields from JSON before comparing.

Difference checker vs text diff

Text diff is line oriented. It can be perfect for source code and plain text, but it can exaggerate JSON changes when indentation, key order, or formatting changes. A JSON difference checker is path oriented. It is better when consumers care about field names, values, and nested structure.

Array order is the main caveat. If an array is reordered, an index-based report may show many changes. In that case, normalize or sort records by an identifier first, then run the checker again.

JSON Diff Tool - canonical structured diff workflow for added, removed, and changed fields.
JSON compare tool online - compare objects, arrays, files, and API payloads by path.
Compare JSON files online - file-focused comparison for fixtures, configs, and exports.
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 checking differences.
JSON Formatter - clean and format JSON before checking differences.
Clean JSON - remove whitespace, nulls, and cleanup noise before review.
Flatten JSON - make deeply nested difference paths easier to scan.
Extract Fields from JSON - compare only the paths that matter.
JSON Schema Validator - confirm the changed payload still matches required structure.

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 difference checker

What counts as a JSON difference?

Difference checking for debugging

Difference checker vs text diff

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