ElevenLabs Conversational AI (now ElevenAgents) vs OpenAI Realtime API
ElevenLabs Conversational AI (now ElevenAgents) vs OpenAI Realtime API: side-by-side comparison of two voice agent platforms systems — architecture, taxonomy, license, pricing, MCP/A2A support, and direct edges.
ElevenLabs Conversational AI (now ElevenAgents) · OpenAI Realtime API
Cost & capability
| ElevenLabs Conversational AI (now ElevenAgents) | OpenAI Realtime API | |
|---|---|---|
| Capability band | competent | frontier |
| Capability composite | 62 | 78 |
| Cost tier | — | premium |
| $/Mtok input | — | 40 |
| $/Mtok output | — | 80 |
| Use cases | Latency Sensitive, Scoped Agentic | Latency Sensitive, Scoped Agentic |
Where they differ (14)
Rows where both sides have data and the values disagree — the shortlist of dimensions that actually distinguish these two systems.
| ElevenLabs Conversational AI (now ElevenAgents) | OpenAI Realtime API | |
|---|---|---|
| Capability band | competent | frontier |
| Capability composite | 62 | 78 |
| Type | Voice-agent platform from a TTS-first vendor (ElevenLabs) | Speech-to-speech LLM API (OpenAI Realtime) |
| Created | 2024-11 (launch) | 2024-10 |
| GitHub | github.com/elevenlabs (SDKs only) | openai/openai-realtime-agents — ~6.9k stars (MIT reference app on Agents SDK), last commit n/a; API itself closed source |
| Pricing | Per-minute usage (Conv AI tier); free + Pro + Enterprise | Audio token-based: $40/$80 per 1M input/output audio tokens (Oct-2024 launch) |
| Funding | $180M Series C Jan-2025 (a16z + ICONIQ; $3.3B val) | OpenAI parent — $40B round Mar-2025 ($300B val) |
| Backend storage | Conversation state in ElevenLabs cloud | Stateless session API; caller manages durability |
| Deployment | Cloud-managed | API (Cloud); no self-host |
| API surface | REST + WebSocket APIs + SDKs (Python, JS, Swift, Android) | WebSocket + WebRTC + REST |
| Multi-tenancy | Multi-tenant cloud | API multi-tenant |
| MCP | yes — hosted ElevenLabs MCP server (recommended); local elevenlabs-mcp server deprecated/archived 2026-08-20 | searched not found |
| Optimised for | Natural-sounding multilingual voice agents leveraging ElevenLabs TTS | Native speech-to-speech with GPT-4o; lowest-latency LLM voice tier |
| Anti-fit | TTS-led — strongest at voice naturalness, less specialised for high-volume telephony routing | Stateless platform — caller builds orchestration, memory, telephony adapter |
At a glance
| ElevenLabs Conversational AI (now ElevenAgents) | OpenAI Realtime API | |
|---|---|---|
| Section | Voice agent platforms | Voice agent platforms |
| Tier | T1 | T1 |
| Type | Voice-agent platform from a TTS-first vendor (ElevenLabs) | Speech-to-speech LLM API (OpenAI Realtime) |
| Created | 2024-11 (launch) | 2024-10 |
| GitHub | github.com/elevenlabs (SDKs only) | openai/openai-realtime-agents — ~6.9k stars (MIT reference app on Agents SDK), last commit n/a; API itself closed source |
| Pricing | Per-minute usage (Conv AI tier); free + Pro + Enterprise | Audio token-based: $40/$80 per 1M input/output audio tokens (Oct-2024 launch) |
| Funding | $180M Series C Jan-2025 (a16z + ICONIQ; $3.3B val) | OpenAI parent — $40B round Mar-2025 ($300B val) |
| Backend storage | Conversation state in ElevenLabs cloud | Stateless session API; caller manages durability |
| Deployment | Cloud-managed | API (Cloud); no self-host |
| API surface | REST + WebSocket APIs + SDKs (Python, JS, Swift, Android) | WebSocket + WebRTC + REST |
| Multi-tenancy | Multi-tenant cloud | API multi-tenant |
| MCP | yes — hosted ElevenLabs MCP server (recommended); local elevenlabs-mcp server deprecated/archived 2026-08-20 | searched not found |
| A2A | searched not found | searched not found |
| OpenTelemetry | searched not found | searched not found |
| Optimised for | Natural-sounding multilingual voice agents leveraging ElevenLabs TTS | Native speech-to-speech with GPT-4o; lowest-latency LLM voice tier |
| Anti-fit | TTS-led — strongest at voice naturalness, less specialised for high-volume telephony routing | Stateless platform — caller builds orchestration, memory, telephony adapter |
Pros & cons
ElevenLabs Conversational AI (now ElevenAgents)
Pros: Best-in-class TTS; $3.3B val parent; SOC 2 + HIPAA; multilingual 30+ languages.
Cons: Newer entrant in agent platform (Nov 2024 launch); strongest at TTS, less mature at full orchestration.
OpenAI Realtime API
Pros: Native speech-to-speech (skips STT/TTS); OpenAI brand + price/perf; WebRTC support.
Cons: Audio token pricing is expensive at scale; stateless (caller builds memory/orchestration); OpenAI-only model choice.