99.9% uptime SLA
The best AI humanizer API.
Turn AI-generated text into natural writing that passes Turnitin, GPTZero and every major detector. One REST call, back in under two seconds.
$100/month includes $100 in API credits
From the team behind Phrasly.ai, as featured in
Humanizer API
Built to run in production.
The engine that powers phrasly.ai, as one REST endpoint. Each release is benchmarked on a fixed test set before it ships.
Humanizer API docsTested against
- Under two seconds
- Typical requests return in under two seconds, fast enough for live products.
- 99.9% uptime SLA
- Runs on Cloudflare's global network, and planned maintenance is announced ahead of time.
- Streaming responses
- Words arrive as they are written, so your interface never waits on a spinner.
- White-label output
- No Phrasly branding or watermarks. Your users only ever see your product.
- Bulk processing
- Run whole libraries through the API, or humanize a CSV of up to 100 documents in the dashboard.
- Per-word pricing
- $0.14 per 1,000 words, with $100 in credits included every month.
AI Detection API
Detection in the same API.
Score any text for AI and get back the sentences that read as AI, so your product can show exactly what to fix.
Detection API docs
- $0.02 per 1,000 words, from the same balance
- The flagged sentences come back with every result
- Bulk scans from a CSV of up to 100 documents
For developers
One request to integrate.
Send text, get human writing back. Call it from your backend, a content pipeline, or a bulk job.
Read the documentation- 1
Create a key
Subscribe and generate an API key in your dashboard.
- 2
Send your text
POST to /api/v1/humanize with the key in the x-api-key header.
- 3
Ship it
Return human-quality writing in your product, pipeline or bulk run.
Pricing
Simple, usage-based pricing.
One plan with credits included, then the same per-word rates.
Business
Everything you need to run humanization in production.
$100/month
Includes $100 in API credits every month
- $0.14 per 1,000 words humanized
- $0.02 per 1,000 words scanned for AI
- Overage at the same rates, no markups
- 99.9% uptime SLA
- Cancel anytime
Need higher volume or custom terms? Talk to sales
Phrasly Ultra
The best AI humanizer.
The smartest humanizer model ever built, with the highest Pangram human scores of any humanizer tested. Available to Business accounts by request.
$0.30per 1,000 words
From your plan's credits. Standard requests stay at $0.14.
- Meaning comes first
- Keep your ideas at the heart of every rewrite.
- Industry-leading bypass
- Built to pass the leading AI detectors, Pangram included, with natural writing.
- Five rewrite modes
- From Gentle to Max on every request. Balanced is the default.
- Text settings
- Optional proofreading and writing nudges, from $0.01 per 1,000 words.
Request access
Tell us who you are and how you will use Ultra. It takes about two minutes, and our team reviews every request by hand.
- 1Send the form
- 2Confirm your email, then we review it
- 3Ultra turns on for your API keys
Questions, answered.
Something else on your mind? Email support@phrasly.ai.
What does the Phrasly API do?
The Phrasly Business API provides two core services: AI Humanization (rewrite AI-generated text to read naturally and pass AI detectors) and AI Detection (analyze text to determine if it was AI-generated). It's the same engine that powers phrasly.ai, exposed as two simple REST endpoints.
Who builds on the Phrasly API?
Hundreds of companies, including AI writing assistants, paraphrasing tools, education platforms, and other humanizers, use Phrasly to power humanization and detection inside their own products. If you've used a humanizer recently, there's a good chance Phrasly was behind it.
Can I use the API for bulk or automated humanization?
Yes. The API is built for volume: call it from your own scripts or content pipeline within your rate limits, or upload a CSV in the dashboard to humanize or scan many texts in one run. Usage is billed per word at the same rates, whatever the volume.
Can I offer humanization under my own brand?
Yes. You call our API from your backend and present the results in your own product, under your own brand. There's no Phrasly attribution, watermarking, or branding in the output. Your users never know we're behind it.
How does billing work?
Your $100/month subscription includes $100 in API credits. That's up to 714,000 humanization words or 5,000,000 detection words. Any usage beyond your included credits is billed as overage at the same per-word rates.
What AI detectors does the humanizer pass?
Our humanizer is tested against all major AI detectors including Turnitin, GPTZero, Copyleaks, Originality.ai, and Winston AI.
Is there a rate limit?
Business accounts have generous rate limits suitable for production use. Contact us if you need higher throughput for enterprise workloads.
How do I get started?
Sign up for a business account, subscribe to the plan, and generate your API key. You can start making API calls immediately.
Start humanizing in minutes.
Join the hundreds of companies building on Phrasly.