API Reference

Limits

Rate Limits

HeyGen's API rate limits depend on the type of token, mode (test or non-test), and specific endpoint:

  • Trial Token: Allows up to daily limit videos per day, maximum video length 60 seconds, with a watermark.
  • API Token test modefor non-Streaming endpoints: Allows up to 60 videos per week/10 per day, maximum video length 60 seconds, with a watermark.
  • API Token non-test modefor non-Streaming endpoints: Video generations are not rate-limited, no watermark, and are deducted from your credit.

The daily limit is 5 for Free Plan users, 8 for Creator Plan users, 10 for Team users, and 20 for Enterprise Plan users.

Limit periods are measured from the time of the first request made, e.g. with daily limits lasting 24 hours from the initial request.

To ensure a smooth interaction with the server and avoid potential throttling, it is recommended to space out your requests.

Streaming API

The Streaming API service operates independently from other API endpoints. After purchasing streaming credits, you will receive an API token. Even if you already have full API access, you need to buy streaming credits to fully access the Streaming API features.

  • Trial Token: allows for 3 concurrent sessions, 300 minutes of streaming per month, and a session limit of 10 minutes.
  • API Token: allows up to 100 concurrent sessions to be created, each minute of the Interactive Avatar speaking consuming 1 API credit.

Advanced API

CategoryAdvanced API
EligibilityContact sales for access and customized options.
ConcurrencyCustomized Concurrency: Simultaneously process up to 10,000 videos.
API SpecificationsIncludes all Basic API features, plus:
- Avatar creation capabilities.
- Video translation proofreading and SRT upload API.
- Customized API solutions tailored to your needs.
  • Avatar creation is not included due to safety controls. Use the HeyGen web interface to create avatars.
  • SRT upload and proofreading services are not available.
  • Trial API Keys available for all users, including free users, to generate avatar videos with a HeyGen watermark. Daily limits: 5 for free users, 8 for creators, 10 for teams, and 20 for enterprise users.

Resource Limits

HeyGen limits the size and format of resources such as images, audio or video. Render errors may occur if resources are invalid.

Resource TypeSuportted formatMax File SizeResolution
VideoMP4100MB<2K
ImageJPG, PNG50MB<2K
AudioWAV, MP350MB

Please ensure:

  • Your resource URL is public and accessible to anyone.
  • The provided asset is in one of the supported formats.
  • Check that the asset file extension aligns with the actual format.
  • Verify that the asset file is not corrupted or misformatted.

Avatar Input Limits

Avatar input can be either text or audio:

  • Text input for avatars should be less than 1500 characters.
  • The duration of audio input for avatars should not exceed 10 minutes (3600 seconds).

Invalid inputs will result in video render failures.

Video Limits

  • The frame rate of video output containing avatars is 25fps.
  • dimension parameter width or height must be less than 4096 and greater than 128.

Limits for Specific APIs

Create Video API:

Streaming Avatar API: