AI voice agents · #9 of 29 · ↑ Pipecat · ↓ Parloa
OpenAI Realtime API
OpenAI Realtime API ranks #9 of 29 in ai voice agents in the week of 21 September 2026, with a visibility score of 8 across ChatGPT, Claude, Gemini and Perplexity. It was named in 15% of the answers we sampled.
sampled: 3 of 4 assistants this week
OpenAI Realtime API shows up in 9 of 60 answers across AI voice agent questions, landing an overall score of 8 out of 100. Claude rates it highest at 22, while ChatGPT gives it just 3 and Perplexity 0. Its strongest showing comes on low-latency questions, where it's named in 2 of 3 answers. It also gets a mention in 1 of 3 answers for best overall voice agents, best for languages other than English, best platform, and best for booking appointments. It's absent from questions about call analytics, receptionists, contact centres, small business phone agents, and open-source frameworks.
Who's talking about you
| assistant | score | named in, this week | usual spot, this week |
|---|---|---|---|
| ChatGPT | 3 | 5% of answers | #7.0 |
| Claude | 22 | 40% of answers | #6.5 |
| Gemini | not sampled this week | ||
| Perplexity | 0 | 0% of answers |
Questions you win
| question | named in | best spot |
|---|---|---|
| Which AI voice agent has the lowest latency? | 2 of 3 | #2 |
| What's the best AI voice agent for languages other than English? | 1 of 3 | #3 |
| What are the best AI voice agent platforms? | 1 of 3 | #6 |
| Which voice AI platform sounds the most natural? | 1 of 3 | #6 |
| What are the best AI voice agents in 2026? | 1 of 3 | #6 |
| Which voice AI platform is best for developers? | 1 of 3 | #8 |
| What's the best AI voice agent for booking appointments? | 1 of 3 | #9 |
| What's the best AI voice agent for inbound customer support calls? | 1 of 3 | #12 |
Questions you lose
| question | who got named instead |
|---|---|
| What's the best AI phone agent for a small business? | Goodcall, Retell AI, Slang.ai |
| Which AI voice agent platform is cheapest per minute? | Retell AI, Bland, Vapi |
| What's the best no-code tool to build a voice AI agent? | Synthflow, Retell AI, Vapi |
| What's the best AI receptionist for answering calls? | Slang.ai, Retell AI, Goodcall |
| What's the best enterprise voice AI platform for contact centres? | PolyAI, Parloa, Cognigy |
| What's the best AI agent for outbound sales calls? | Retell AI, Bland, Vapi |
| What's the best AI voice agent for a restaurant or clinic taking bookings? | Slang.ai, PolyAI, Retell AI |
| What's the best voice AI that connects to my CRM? | Retell AI, Vapi, Bland |
| What's the best open-source voice AI agent framework? | LiveKit Agents, Pipecat, Vocode |
| What's the best voice AI platform with its own phone numbers and telephony? | Vapi, Retell AI, Bland |
| What's the best AI voice agent that can transfer to a human? | Retell AI, PolyAI, Vapi |
| What's the best voice AI platform for call analytics and transcripts? | Dialpad |
Assistants cited 14 pages for questions in this category that name your rivals and not you. See all sources for AI voice agents.
In their words
- ChatGPT“If you're choosing a stack specifically for the most natural, low-latency conversation, I'd compare Dasha, Retell, Telnyx, ElevenLabs, and OpenAI Realtime rather than relying on vendor-published latency numbers.”
- Claude“OpenAI Realtime API (GPT-4o/4o-mini realtime) — ~300ms typical response latency, and generally the best latency/intelligence tradeoff.”
- Claude“OpenAI Realtime API — native speech-to-speech, low latency, preserves tone and interruption handling”
Closest rivals
- OpenAI Realtime API vs Parloa8
- OpenAI Realtime API vs Slang.ai8
- OpenAI Realtime API vs Cognigy6
- OpenAI Realtime API vs Goodcall6
- OpenAI Realtime API vs Thoughtly6
All OpenAI Realtime API alternatives · Full AI voice agents leaderboard · Sources