LLM Reference

Claude Opus 4.5 vs Claude Sonnet 4.6

Claude Opus 4.5 (2025) and Claude Sonnet 4.6 (2026) are frontier-tier reasoning models from Anthropic. Claude Opus 4.5 ships a 200k-token context window, while Claude Sonnet 4.6 ships a 1m-token context window. On MMLU PRO, Claude Opus 4.5 leads by 1.6 pts. On pricing, Claude Sonnet 4.6 costs $3/1M input tokens versus $5/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Claude Sonnet 4.6 is ~67% cheaper at $3/1M; pay for Claude Opus 4.5 only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude Opus 4.5Claude Sonnet 4.6
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$25/1M tokens$15/1M tokens
Provider routes6 tracked6 tracked
Shared benchmarksMMLU PRO leader7 shared

Decision tradeoffs

Choose Claude Opus 4.5 when...
  • Claude Opus 4.5 holds a shared-benchmark lead on MMLU PRO, ahead by 1.6 points.
  • Local decision data tags Claude Opus 4.5 for Coding, RAG, and Agents.
Choose Claude Sonnet 4.6 when...
  • Claude Sonnet 4.6 holds a shared-benchmark lead on Google-Proof Q&A, ahead by 2.9 points.
  • Claude Sonnet 4.6 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Claude Sonnet 4.6 has the lower cheapest tracked output price at $15/1M tokens.
  • Claude Sonnet 4.6 uniquely exposes Computer use and Parallel agents in local model data.
  • Local decision data tags Claude Sonnet 4.6 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 Claude Sonnet 4.6

Claude Opus 4.5

$10,250

Cheapest tracked route/tier: Microsoft Foundry

Claude Sonnet 4.6

$6,150

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $4,100. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Opus 4.5 -> Claude Sonnet 4.6
  • Provider overlap exists on OpenRouter, Anthropic, and AWS Bedrock; start route-level A/B tests there.
  • Claude Sonnet 4.6 is $10/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Claude Sonnet 4.6 adds Computer use and Parallel agents in local capability data.
Claude Sonnet 4.6 -> Claude Opus 4.5
  • Provider overlap exists on Microsoft Foundry, Anthropic, and GCP Vertex AI; start route-level A/B tests there.
  • Claude Opus 4.5 is $10/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Computer use and Parallel agents before moving production traffic.

Specs

Specification
Released2025-11-012026-02-17
Context window200k1m
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
WeightsNot releasedNot released
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-122025-08

Pricing and availability

Pricing attributeClaude Opus 4.5Claude Sonnet 4.6
Input price$5/1M tokens$3/1M tokens
Output price$25/1M tokens$15/1M tokens
Providers

Capabilities

CapabilityClaude Opus 4.5Claude Sonnet 4.6
VisionYesYes
MultimodalYesYes
ReasoningYesYes
JSON / Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoYes
Parallel agentsNoYes

Benchmarks

BenchmarkClaude Opus 4.5Claude Sonnet 4.6
MMLU PRO88.987.3
SWE-bench Verified80.979.6
Google-Proof Q&A87.089.9
Massive Multi-discipline Multimodal Understanding80.783.6
ARC-AGI-237.658.3
Chatbot Arena1466.01459.0
MMMU Pro73.975.6

Continue comparing

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