Data tool

API Response Corruptor

Generate bad API responses on purpose so you can test frontend error handling, schema validation, retry logic, importers, and edge cases.

Runs Locally

This tool runs in your browser. Files never leave your device.

API response input

Drop a JSON/TXT file here or paste a response body below.

Open file

Drag and drop a .json or .txt file anywhere inside this input card.

Size

680 B

Lines

Keys

Objects

Arrays

Corrupted response

490 B output · valid JSON

Damage presetResponse shapeSeed

Validation status

Output can still be parsed as JSON, but its values/schema may be intentionally wrong.

{
  "status": 400,
  "requestId": "req_9f43a8c2",
  "data": {
    "user": {
      "id": null,
      "name": "Laramie Williamson",
      "email": "laramie@exaple.com",
      "role": null,
      "active": true,
      "createdAt": "2026-06-20T15:30:00Z"
    },
    "subscriptions": [
      null,
      {
        "id": "sub_002",
        "plan": "storagestoragestoragestorage",
        "currency": "USD",
        "renewing": null
      }
    ]
  },
  "meta": {
    "page": null
  },
  "ok": 0
}

API damage controls

Tune the exact failure modes you want your app to survive.

Fields removed14%Fields nulled16%Types swapped18%Keys renamed12%Collections emptied10%Array items duplicated12%Arrays reordered30%Strings mutated16%Extreme numbers12%Status/errors changed25%Latency/retry fields18%Syntax breakage6%

What this tool does

API Response Corruptor creates intentionally broken API responses for testing applications, integrations, parsers, and validation systems. Simulate real-world failures that occur when APIs return incomplete, invalid, or unexpected data. Developers can use this tool to strengthen error handling and improve application reliability.