Compare realtime APIs

Pick up to four APIs from any category and see them side by side.

NVIDIA VSS blueprint / Cosmos Reason
NVIDIA
Synthesia Interactive Avatars
Synthesia
Odyssey API (interactive world model video)
Odyssey
CategoryAvatars + videoAvatars + videoAvatars + video
StatusPreviewGABeta
Est. per minuten/an/an/a
How that was worked outSelf-hosted; depends on your GPUs and licenceNo published realtime rate foundNo public price list found; pricing page 404s
Pricing modelfreesubscriptionsubscription
Free tierPreview API credits for new accounts.None found for interactive avatars.Free accounts get 5 concurrent streams; hour quota not published.
Connects byRTSPLiveKitWebRTC, WebSocket
Audio inn/aYour LiveKit agent's TTS audioNone
Audio outn/aYour TTSNot documented
Languagesn/aNot captured.Text prompts.
Latency (vendor claim)Chunk-based (user-defined chunk duration); not frame-level realtime.Not captured.Third-party reports about 20-22 fps at 720p (frame every ~50 ms); no official latency figure.
Key limits
  • No hosted realtime streaming endpoint confirmed
  • Up to 5 avatar IDs per session
  • Each stream max 150 s by default (start a new stream to continue)
  • Each connection max 60 min
  • Idle connection with no active stream disconnects after 15 min
  • Up to 10 queued simulation jobs
High-severity warnings
  • None
  • No public realtime price
  • No published pricing
ComplianceDepends on your deployment.Not verified in this pass.Not verified.
Self-hostableYesNoNo
Last checked2026-10-102026-10-102026-10-10
Key numbers and features
Session $/min---
Entry plan $/mo-$89-
Free tierYesNoYes
Free credit $---
Custom avatar---
From photo---
Own LLM-Yes-
Own voice-Yes-
Interrupts---
Resolution p--720
FPS--20
CPU onlyNo--
Latency ms---
Languages---
Max session min--2.5
Concurrency--5
WebRTCNoYesYes
WebSocket--Yes
Phone / SIP---
HIPAA---
SOC 2---
EU data---
Self-hostYesNoNo
Open weightsNoNoNo
High warnings011