Claude Sonnet 4.6 vs Gemini 3.1 Pro Preview
Compare Claude Sonnet 4.6 and Gemini 3.1 Pro Preview on the metrics that decide an agent workload.
| Metric | Claude Sonnet 4.6 | Gemini 3.1 Pro Preview |
|---|---|---|
| Provider | Anthropic | Google Gemini |
| Input / 1M | $3.00 | $2.00 |
| Output / 1M | $15.00 | $12.00 |
| Cache read / 1M | $0.30 (−90%) | $0.20 (−90%) |
| Reuse-adj @55% | $4.89 | $3.76 |
| Context | 1M | 1M |
| Cache capture | 91% | 82% |
| Warm TTFT | 190ms (−65%) | 360ms (−56%) |
| Quality index | 90 | 94 |
Teal marks the better value in each row. Reuse-adjusted assumes 55% prefix reuse and a 25% output share.
Pick Claude Sonnet 4.6 when it answers faster on warm cache hits, it captures more of the available reuse.
Pick Gemini 3.1 Pro Preview when it scores higher on the composite quality index, it is cheaper once prefix reuse is priced in, it carries the larger 1M context window.
Gemini 3.1 Pro Preview wins on both reuse-adjusted cost and quality here, so it is the default pick. Reach for Claude Sonnet 4.6 only when a specific constraint (modality, latency floor, or licensing) forces it.
Claude Sonnet 4.6 vs Gemini 3.1 Pro Preview, answered.
Is Claude Sonnet 4.6 or Gemini 3.1 Pro Preview cheaper?
At 55% prefix reuse, Claude Sonnet 4.6 blends to about $4.89 per 1M tokens and Gemini 3.1 Pro Preview to about $3.76. Gemini 3.1 Pro Preview is cheaper on that basis.
Which has the larger context window?
Gemini 3.1 Pro Preview has the larger window: 1M vs 1M tokens.
Which captures more reuse?
Claude Sonnet 4.6 shows higher measured cache capture (91% vs 82%) in the Zumik corpus.
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