Which is faster, OpenAI or xAI?

xAI is faster, 0.59s sooner. The best OpenAI result is GPT Realtime 2.1 at 1.94s, and the best xAI result is Grok Voice 3.0 at 1.34s, on response time.

Which OpenAI and xAI models were tested?

OpenAI: GPT Realtime 2.1, GPT-Live 1 + GPT-6 Sol, GPT Realtime 2.1 Mini. xAI: Grok Voice Think Fast 2.0, Grok Voice 3.0. Every model ran the same tests on Speech-to-speech.

Bench

OpenAIvsxAI

OpenAI is ahead on success rate, agent responses, data accuracy, interruption and cost, and xAI on reliability, calls where the agent went quiet and response time.

Last updated Oct 14, 2026Methodology by Dileep Chagam

Who is better at what

Each row sets OpenAI's best model against xAI's best on that measure.

OpenAIxAI

Reliability79.3%GPT Realtime 2.181.7%Grok Voice 3.0
Success rate89.0%GPT Realtime 2.186.6%Grok Voice 3.0
Agent responses100.0%GPT-Live 1 + GPT-6 Sol97.2%Grok Voice 3.0
Data accuracy92.0%GPT Realtime 2.187.3%Grok Voice 3.0
Went quiet2.5%GPT Realtime 2.1 Mini0.0%Grok Voice 3.0
Interruption4.99GPT Realtime 2.1 Mini4.98Grok Voice 3.0
Response time1.94sGPT Realtime 2.11.34sGrok Voice 3.0
Cost / min$0.020GPT Realtime 2.1 Mini$0.080Grok Voice Think Fast 2.0

Model against model

OpenAI vs xAI FAQ

Is OpenAI or xAI better for speech-to-speech?

xAI is ahead, 2.4 points higher. The best OpenAI result is GPT Realtime 2.1 at 79.3%, and the best xAI result is Grok Voice 3.0 at 81.7%, on reliability.

xAI is ahead, 2.4 points higher. The best OpenAI result is GPT Realtime 2.1 at 79.3%, and the best xAI result is Grok Voice 3.0 at 81.7%, on reliability.
xAI is faster, 0.59s sooner. The best OpenAI result is GPT Realtime 2.1 at 1.94s, and the best xAI result is Grok Voice 3.0 at 1.34s, on response time.
OpenAI: GPT Realtime 2.1, GPT-Live 1 + GPT-6 Sol, GPT Realtime 2.1 Mini. xAI: Grok Voice Think Fast 2.0, Grok Voice 3.0. Every model ran the same tests on Speech-to-speech.