Compare realtime APIs
Pick up to four APIs from any category and see them side by side.
| OpenAI Agents SDK (voice / realtime agents) OpenAI | TEN Framework Agora / TEN community | Vonage Voice/Video API AI connectors (Audio Connector) + AI Studio Vonage (Ericsson) | |
|---|---|---|---|
| Category | Platforms | Platforms | Platforms |
| Status | GA | GA | GA |
| Est. per minute | n/a | n/a | n/a |
| How that was worked out | Cost is the OpenAI model bill, priced in the realtime models segment. | Depends entirely on chosen transport and providers; no vendor figure. | Could not verify current Vonage per-minute voice rates. Vapi's pricing page lists Vonage telephony at $0.00814/min as a pass-through reference. |
| Pricing model | free/open | free/open | usage |
| Free tier | Open source. | Open source. | Not verified. |
| Connects by | WebRTC, WebSocket, SIP | WebRTC, SIP | WebSocket, WebRTC, SIP, PSTN |
| Audio in | Mic via WebRTC in browser; PCM/G.711 over WebSocket | Agora RTC by default; other extensions possible | Linear PCM 8/16/24 kHz over WebSocket |
| Audio out | Same | Same | Same (bidirectional) |
| Languages | Per OpenAI realtime/transcription models. | Depends on providers; turn detection supports English and Chinese. | Depends on your models. |
| Latency (vendor claim) | Model-dependent. | No verified number. | No verified number. |
| Key limits |
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| High-severity warnings |
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| Compliance | Per OpenAI API terms (not covered here). | N/A (self-hosted). | Not verified in this research. |
| Self-hostable | Yes | Yes | No |
| Last checked | 2026-10-10 | 2026-10-10 | 2026-10-10 |
| Key numbers and features | |||
| Platform $/min | $0 | $0 | - |
| All-in price | No | No | No |
| Entry plan $/mo | $0 | $0 | $0 |
| Free tier | Yes | Yes | - |
| Free credit $ | - | - | - |
| Phone numbers | No | No | Yes |
| Own LLM | - | Yes | Yes |
| Own keys | - | Yes | Yes |
| No-code | - | Yes | Yes |
| Recording | - | - | - |
| Noise cancel | - | - | - |
| Smart turns | - | Yes | - |
| Latency ms | - | - | - |
| Languages | - | - | - |
| Max session min | - | - | - |
| Concurrency | - | - | - |
| WebRTC | Yes | Yes | Yes |
| WebSocket | Yes | - | Yes |
| Phone / SIP | Yes | Yes | Yes |
| HIPAA | - | - | - |
| SOC 2 | - | - | - |
| EU data | - | - | - |
| Self-host | Yes | Yes | No |
| Open weights | Yes | Yes | No |
| High warnings | 0 | 0 | 0 |