Claude Sonnet 5 vs Gemini 3.1 Pro

Anthropic against Google, costed on the same three workloads. Claude Sonnet 5 is cheaper on all three workloads.

Monthly bill, side by side

WorkloadClaude Sonnet 5Gemini 3.1 ProDifference
Support chatbot
2,500 six-turn conversations a day
$8,055 $8,865 $810 (+10%)
Document summariser
1,000 single-shot summaries a day
$972 $1,020 $48.00 (+5%)
Coding agent
200 twelve-turn sessions a day
$5,616 $5,976 $360 (+6%)

No prompt caching and no batch discount on either side, so the comparison is like for like. Both figures assume 30 days a month.

The rate cards

Claude Sonnet 5Gemini 3.1 Pro
Input, per 1M tokens$3$2
Output, per 1M tokens$15$12
Cached input$0.3$0.2
Context window1M1.05M
Maximum output128K66K
Reasoning modelyesyes
Visionyesyes

Run this comparison on your own numbers

Full detail: Claude Sonnet 5 pricing · Gemini 3.1 Pro pricing