Claude Sonnet 4.5 (2025-09-29) vs Gemini 3.1 Pro preview
Claude Sonnet 4.5 (2025-09-29) vs Gemini 3.1 Pro preview: Gemini 3.1 Pro preview is cheaper by 33% on average. Claude Sonnet 4.5 (2025-09-29) from Anthropic (200,000-token context, reasoning, tool calls) vs. Gemini 3.1 Pro preview from Google Vertex AI (1,048,576-token context, reasoning, tool calls). Use Agent Command Center to A/B both in shadow mode and pick the winner per workload.
Side-by-side cost
Live workload comparison
Same workload run through both models. The cheaper one is highlighted.
3,000
01,048,576
400
065,536
5,000
01,000,000
At this workload, Gemini 3.1 Pro preview is 28% cheaper than Claude Sonnet 4.5 (2025-09-29) — a savings of $639/month ($7,670/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
model: gemini-3-1-pro-preview
provider: vertex-ai
fallback:
model: claude-sonnet-4-5-20250929
provider: anthropic
shadow: { sample_rate: 0.05 } # mirror 5% of traffic to compare quality live| Claude Sonnet 4.5 (2025-09-29) | Gemini 3.1 Pro preview | |
|---|---|---|
| Input price | $3.00/M | $2.00/M |
| Output price | $15.00/M | $12.00/M |
| Context window | 200,000 | 1,048,576 |
| Max output | 64,000 | 65,536 |
| Function calling | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio input | — | ✓ |
| Reasoning | ✓ | ✓ |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Pricing verified | May 12, 2026 | May 12, 2026 |
Benchmark comparison
Side-by-side public benchmark scores. Greener bar = winner.
Chatbot Arena ELOgeneral
Claude Sonnet 4.5 (2025-09-29)
1,454
Gemini 3.1 Pro preview
1,492
AIME 2025math
Claude Sonnet 4.5 (2025-09-29)
100.0%
Gemini 3.1 Pro preview
—
GPQA Diamondreasoning⚠ different settings
Claude Sonnet 4.5 (2025-09-29)
84.4%
Gemini 3.1 Pro preview
94.3%
HumanEvalcode
Claude Sonnet 4.5 (2025-09-29)
93.7%
Gemini 3.1 Pro preview
—
MATH-500math
Claude Sonnet 4.5 (2025-09-29)
88.0%
Gemini 3.1 Pro preview
—
IFEvalgeneral
Claude Sonnet 4.5 (2025-09-29)
87.6%
Gemini 3.1 Pro preview
—
MMLU-Proreasoning
Claude Sonnet 4.5 (2025-09-29)
87.4%
Gemini 3.1 Pro preview
—
BFCL v3agent
Claude Sonnet 4.5 (2025-09-29)
85.7%
Gemini 3.1 Pro preview
—
SWE-bench Verifiedagent⚠ different settings
Claude Sonnet 4.5 (2025-09-29)
82.0%
Gemini 3.1 Pro preview
80.6%
MMMU-Promultimodal
Claude Sonnet 4.5 (2025-09-29)
—
Gemini 3.1 Pro preview
80.5%
AIME 2024math
Claude Sonnet 4.5 (2025-09-29)
79.6%
Gemini 3.1 Pro preview
—
Aider Polyglotcode
Claude Sonnet 4.5 (2025-09-29)
77.8%
Gemini 3.1 Pro preview
—
MMMUmultimodal
Claude Sonnet 4.5 (2025-09-29)
77.6%
Gemini 3.1 Pro preview
—
ARC-AGI-2reasoning
Claude Sonnet 4.5 (2025-09-29)
—
Gemini 3.1 Pro preview
77.1%
τ-bench (retail)agent
Claude Sonnet 4.5 (2025-09-29)
75.4%
Gemini 3.1 Pro preview
—
LiveCodeBenchcode
Claude Sonnet 4.5 (2025-09-29)
67.4%
Gemini 3.1 Pro preview
—
τ-bench (airline)agent
Claude Sonnet 4.5 (2025-09-29)
55.0%
Gemini 3.1 Pro preview
—
Humanity's Last Examreasoning
Claude Sonnet 4.5 (2025-09-29)
—
Gemini 3.1 Pro preview
44.4%