LLM Reference

Claude Sonnet 4.5 vs Gemini 2.5 Pro

Claude Sonnet 4.5 (2025) and Gemini 2.5 Pro (2025) are frontier-tier reasoning models from Anthropic and Google DeepMind. Claude Sonnet 4.5 ships a 200k-token context window, while Gemini 2.5 Pro ships a 1m-token context window. On MMLU PRO, Gemini 2.5 Pro leads by 0.2 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Gemini 2.5 Pro fits 5x more tokens; pick it for long-context work and Claude Sonnet 4.5 for tighter calls.

Decision scorecard

Local evidence first
SignalClaude Sonnet 4.5Gemini 2.5 Pro
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, multimodal apps, and tool-calling agents
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window200k1m
Cheapest output$15/1M tokens$10/1M tokens
Provider routes8 tracked4 tracked
Shared benchmarks4 sharedMMLU PRO leader

Decision tradeoffs

Choose Claude Sonnet 4.5 when...
  • Claude Sonnet 4.5 holds a shared-benchmark lead on SWE-bench Verified, ahead by 13.4 points.
  • Claude Sonnet 4.5 has broader tracked provider coverage for fallback and route flexibility.
  • Local decision data tags Claude Sonnet 4.5 for Coding, RAG, and Agents.
Choose Gemini 2.5 Pro when...
  • Gemini 2.5 Pro holds a shared-benchmark lead on MMLU PRO, ahead by 0.2 points.
  • Gemini 2.5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 2.5 Pro has the lower cheapest tracked output price at $10/1M tokens.
  • Gemini 2.5 Pro uniquely exposes Code execution in local model data.
  • Local decision data tags Gemini 2.5 Pro for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Gemini 2.5 Pro

Claude Sonnet 4.5

$6,150

Cheapest tracked route/tier: Microsoft Foundry

Gemini 2.5 Pro

$3,500

Cheapest tracked route/tier: Google AI Studio <=200K tokens

Estimated monthly gap: $2,650. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Sonnet 4.5 -> Gemini 2.5 Pro
  • Provider overlap exists on GCP Vertex AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
  • Gemini 2.5 Pro is $5/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Gemini 2.5 Pro adds Code execution in local capability data.
Gemini 2.5 Pro -> Claude Sonnet 4.5
  • Provider overlap exists on GCP Vertex AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
  • Claude Sonnet 4.5 is $5/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Code execution before moving production traffic.

Specs

Specification
Released2025-09-292025-06-17
Context window200k1m
Parameters——
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
WeightsNot releasedNot released
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-122025-01

Pricing and availability

Pricing attributeClaude Sonnet 4.5Gemini 2.5 Pro
Input price
0-200,001t
$3/1M tokens
200,001t+
$6/1M tokens
<=200K tokens
$1.25/1M tokens
Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens.
>200K tokens
$2.50/1M tokens
Higher Gemini 2.5 Pro tier for prompts above 200K tokens.
Output price
0-200,001t
$15/1M tokens
200,001t+
$22.50/1M tokens
<=200K tokens
$10/1M tokens
Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens.
>200K tokens
$15/1M tokens
Higher Gemini 2.5 Pro tier for prompts above 200K tokens.
Providers
Microsoft FoundryAnthropicSnowflake CortexGCP Vertex AIAWS BedrockReplicate API
Google AI StudioGCP Vertex AIOpenRouterVercel AI Gateway

Capabilities

CapabilityClaude Sonnet 4.5Gemini 2.5 Pro
VisionYesYes
MultimodalYesYes
ReasoningYesYes
JSON / Tool useYesYes
Structured outputsYesYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkClaude Sonnet 4.5Gemini 2.5 Pro
MMLU PRO86.086.2
SWE-bench Verified77.263.8
Google-Proof Q&A83.486.4
Massive Multi-discipline Multimodal Understanding77.881.7

Continue comparing

Model pages
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Last reviewed: 2026-07-26. Data sourced from public model cards and provider documentation.