AI Humanizer API Documentation

• One standardized REST endpoint
• 50+ languages, auto-detected
• AI-detection aware (returns flag)
• Predictable word-priced billing
• Per-account API keys with scope
• Webhook events & usage analytics

1. 1

   Get your API key

   Create an account on humanwrite.io and copy your key from the dashboard.

2. 2

   Make your first request

   POST /v1/humanize with a Content-Type: application/json body.

   cURLJavaScriptPython

   curl https://api.humanwrite.io/v1/humanize \
     -H "Authorization: Bearer $HUMANWRITE_API_KEY" \
     -H "Content-Type: application/json" \
     -d '{
       "input": "AI-generated draft paragraph...",
       "tone": "natural",
       "language": "en-US",
       "detect": true
     }'

3. 3

   See the response

   The API returns a single formatted JSON response.

   {
     "id": "hum_a1b2c3d4e5f6",
     "created": 1778533901580,
     "result": "Artificial intelligence has changed the game in content creation and communication.",
     "score": 82,
     "input_words": 14,
     "words_remaining": {
       "included": 399986,
       "topup": 0,
       "total": 399986
     }
   }

Authorization header

GET /v1/humanize HTTP/1.1
Host: api.humanwrite.io
Authorization: Bearer hw_live_3f4c5e6a7b8d9e0f
Content-Type: application/json

Status codes you may receive.

All errors return an application/json envelope with a machine-readable code and a human-readable message. Below is the full reference.

{ "error": "No active subscription" }

{
  "error": "Insufficient word balance",
  "words_remaining": {
    "included": 12,
    "topup": 0,
    "total": 12
  }
}

{ "error": "Invalid request: ..." }

{ "error": "The model parameter is not available" }

{ "error": "Input exceeds per-request limit of 2000 words for your plan. Received ~2500 words." }

{ "error": "Content blocked: sexual" }

{ "error": "Rate limit exceeded for your plan (api_standard -> 40/min). api_standard: 40/min | api_premium: 120/min" }

{ "error": "Too many failed authentication attempts" }

{ "error": "Too many queued requests. Please retry shortly." }

Send a block of text and receive a human-style rewrite. Optionally returns an AI score for downstream flagging.

curl https://api.humanwrite.io/v1/humanize \
  -H "Authorization: Bearer $HUMANWRITE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "input": "AI-generated draft paragraph...",
    "tone": "natural",
    "language": "en-US",
    "detect": true
  }'

{
  "id": "hum_a1b2c3d4e5f6",
  "created": 1778533901580,
  "result": "AI has changed how we create content and communicate online.",
  "score": null,
  "input_words": 14,
  "words_remaining": {
    "included": 124986,
    "topup": 0,
    "total": 124986
  }
}

curl https://api.humanwrite.io/v1/humanize \
  -H "Authorization: Bearer $HUMANWRITE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "input": "AI-generated draft paragraph...",
    "tone": "natural",
    "language": "en-US",
    "detect": true
  }'

Per-key analytics with time-series breakdowns.

curl "https://api.humanwrite.io/v1/usage" \
  -H "Authorization: Bearer $HUMANWRITE_API_KEY"

We auto-detect the input language and return natural, fluent output in the same language. Pass an explicit ISO-639-1 code inlanguage for deterministic behavior.

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