Heygen

HeyGen makes AI avatar video generation accessible via API: choose an avatar (100+ stock or custom clone), provide a script, select a voice, and HeyGen renders a photorealistic presenter video. For agents creating content at scale: generate product demo videos, training modules, localized content (HeyGen video translation API translates into 30+ languages with lip-sync). Streaming Avatar enables real-time AI avatar interactions. Async generation model: POST video job → webhook or poll → download URL. Competitive with Synthesia. Confidence is docs-derived.

REST API at api.heygen.com/v1 (v2 for some). Resources: video.generate, video.status, video_translate.create, avatar.list, voice.list, streaming.new. POST /v1/video.generate creates a video ({video_inputs: [{character: {type: avatar, avatar_id, avatar_style}, voice: {type: text, input_text, voice_id}}, ...], dimension, test: false}). GET /v1/video_status.get?video_id={id} polls status (pending/processing/completed/failed). POST /v2/video_translate creates a translation job ({video_url, output_language}). GET /v2/avatar.list lists available stock avatars. GET /v1/voice.list lists TTS voices.

API key auth: X-Api-Key: {api_key} header. Keys from HeyGen Dashboard → Settings → API. Account-scoped. HTTPS enforced. No OAuth2. Trial API keys have limited credits (test videos have watermark). Production keys require paid plan. Video download URLs are time-limited (presigned). Custom avatar creation requires identity verification and consent process.

Standard HTTP status codes with JSON error bodies ({code, message}). 400 for invalid avatar_id or voice_id (use avatar/voice list endpoints to validate first). Video generation async: poll GET /v1/video_status.get every 15–30 seconds. Typical generation time: 1–3 minutes for 1-minute video. Failed videos have error field. Rate limits: plan-dependent; concurrent video generation limited. HeyGen uptime at status.heygen.com. Video quality is production-grade for stock avatars.

docs.heygen.com provides API reference for all endpoints (video generation, translation, streaming, avatar/voice listing), code examples, and integration guides. Getting started: create account, get API key (trial plan), first video generation in sandbox in under 20 minutes. No official SDK — REST is straightforward. HeyGen provides Postman collection for API exploration. Community support via HeyGen Discord and support chat.