AI Humanizer API
Humanize AI-generated text at scale with a single REST API call. The Ultra Humanizer API converts output from any LLM into natural, human-sounding writing that reads as genuinely written by a person, with full control over style, depth, voice, and language.
curl -X POST https://api.ultrahumanizer.com/api/humanize \
-H "Content-Type: application/json" \
-d '{
"text": "The findings suggest a correlation between the variables.",
"client_key": "uk_your_api_key",
"style": "academic",
"context": "research paper",
"language": "english"
}'Why developers choose the Ultra Humanizer API
A production-ready humanizer API built to drop into any content pipeline, agent framework, or app to humanize AI text at scale without managing prompts or models.
One REST call
Send a single POST request with your text and get human-sounding output back. Works with any LLM, including ChatGPT, Claude, Gemini, Llama, or your own pipeline.
Beats every major detector
Output is rebuilt at the sentence and structure level to read as genuinely human across Turnitin, Pangram, Originality.ai, Copyleaks, GPTZero, and more.
Full parameter control
Every control from the web app is exposed: style, depth, formality, variation, voice profile, locked phrases, citation preservation, and markdown handling.
12+ languages
Humanize content in English, Spanish, French, German, Portuguese, Japanese, Chinese, and more from the same endpoint.
Streaming responses
Set stream: true to receive newline-delimited JSON as each sentence is humanized, ideal for responsive product UIs.
Private by design
Your text is never stored or used for training. Requests are processed and immediately discarded after the response is returned.
Integrate the humanizer API in minutes
Get your API key
Sign up free for 1,000 credits and generate a key in your account dashboard. No card required.
Send a request
POST your text and configuration to /api/humanize. Text in, humanized text out.
Ship to production
Handle the JSON response, track usage via /api/usage, and scale with pay-once credits that never expire.
const res = await fetch("https://api.ultrahumanizer.com/api/humanize", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
text: aiGeneratedDraft,
client_key: process.env.ULTRAHUMANIZER_KEY,
style: "professional",
context: "blog post",
}),
});
const { result } = await res.json();
// => human-sounding, detector-ready textBuilt for content pipelines and AI products
Wire the humanizer API into your CMS, agent workflow, or SaaS to humanize AI text the moment it is generated. Content teams use it to publish drafts that read naturally and clear AI detectors; product teams use it to add a humanize feature without training their own models. Each request draws from a shared credit balance across all of your API keys, so you can scale from a prototype to production on one account.
The same engine as the web Humanizer
The API is not a stripped-down version of the product. It exposes every parameter available in the web Humanizer, including style, depth, formality, variation, voice profiles, locked phrases, and citation preservation. Prototype your settings in the playground, then copy them straight into your API calls.
Humanizer API FAQ
What is the Ultra Humanizer API?
It is a REST API that turns AI-generated text into natural, human-sounding writing. You send text to a single POST endpoint with your API key and configuration, and receive humanized output that reads as genuinely written by a person.
How do I get started with the humanizer API?
Create a free account to get 1,000 credits, generate an API key in your dashboard, and send your first POST request to /api/humanize. No card is required to start.
How is the API priced?
You buy pay-once credit packs that never expire. Standard depth costs 1 credit per input word; enhanced depth costs 2. There is no subscription. See the pricing page for current packs.
Will text humanized through the API pass AI detectors?
Yes. API output uses the same engine as the web Humanizer and maintains a 99.8% verified pass rate against major detectors. Results depend on input quality, so always review before publishing.
What languages and content types does the API support?
The API supports 12+ languages and works for essays, articles, marketing copy, emails, and reports. Choose a style and context per request to match your use case.
Is there a rate limit?
Each account is rate limited to 100 requests per second by default, shared across all of its API keys. If you exceed the limit you receive a 429 response, so retry with exponential backoff. Contact support to extend your limit for production workloads.
Start building with the humanizer API
Get 1,000 credits on signup. No card required. Generate a key and make your first call in minutes.