Gemini 3.1 Flash Live Preview vs Grok Voice 3.0

Grok Voice 3.0 is more reliable, by 8.6 points. Gemini 3.1 Flash Live Preview handled 24 of 70 real callers well on all three runs, and Grok Voice 3.0 30. A caller only counts when every run of the call scored 80 or more.

For a voice agent, Grok Voice 3.0, since it handles more real callers well on every run. Grok Voice 3.0 is ahead on ELO rating, hearing score, turn taking score, speaking score, task handling score, reliability, calls handled well, calls fully resolved, calls where the agent went quiet and median latency, and Gemini 3.1 Flash Live Preview on cost.

Grok Voice 3.0, by 10.0 points higher. Gemini 3.1 Flash Live Preview fully resolved 24.8% of calls and Grok Voice 3.0 34.8%. A call counts only when every step the caller needed was done.

No. Grok Voice 3.0 starts replying 1.46s sooner at the median. Gemini 3.1 Flash Live Preview takes 3.06s at the median and 3.86s at p90; Grok Voice 3.0 takes 1.60s and 1.94s. Both are measured on the call audio, from the caller finishing to the agent starting to reply.

Grok Voice 3.0, by 0.5 points. The agent went quiet for 10 seconds or more on 7.6% of Gemini 3.1 Flash Live Preview calls and 7.1% of Grok Voice 3.0 calls.

Gemini 3.1 Flash Live Preview is $0.010 cheaper a minute. Gemini 3.1 Flash Live Preview costs $0.070 a minute of call and Grok Voice 3.0 $0.080, at each vendor's published rates.

Cekura ran both as the whole agent with the same prompt, tools and phone connection. Both took the same 70 recorded real human callers on live calls, three times each. Each call is graded on 25 skills across Hearing, Turn Taking, Task Handling and Speaking, and passes at a score of 80 out of 100.