Create Proofread Session
Creates a proofread session that extracts editable subtitles from a video before final rendering. Lets you review and edit translation subtitles before committing to the full render. See the proofread section in the Video Translation guide. Next steps: Download SRT, Upload SRT, Generate Final Video.
Documentation Index
Fetch the complete documentation index at: https://heygen-1fa696a7.mintlify.app/llms.txt
Use this file to discover all available pages before exploring further.
Authorizations
HeyGen API key. Obtain from your HeyGen dashboard.
Headers
Optional client-supplied key for safely retrying mutations. Subsequent calls within 24 hours that share this key replay the original response — even if the request body differs slightly (a warning is logged). A retry that arrives while the original is still in flight gets a 409 request_in_progress. Keys must be 1–255 characters from [A-Za-z0-9_:.-]; a UUID is a safe default. Scope is per-endpoint and per-resource: the same key on a different route or path parameter is independent.
1 - 255^[A-Za-z0-9_\-:.]{1,255}$Body
Request body for POST /v3/video-translations/proofreads.
Asset input via publicly accessible HTTPS URL.
- AssetUrl
- AssetId
Target language codes. Use one for single proofread, multiple for batch.
1Title for the proofread job
Custom brand voice ID. Requires brand voice setup.
Number of speakers (improves speaker separation)
Project/folder ID to organize proofread into
Allow dynamic duration adjustment
Remove background music
Enhance speech quality
Asset input via publicly accessible HTTPS URL.
- AssetUrl
- AssetId
Translation quality mode: 'speed' (faster) or 'precision' (higher quality)
speed, precision Preserve the source video's encoding specs (resolution, bitrate)
Response
Successful response
Response for POST /v3/video-translations/proofreads.

