Claude Sonnet 4.5 vs Claude Opus 4.6

Detailed pricing comparison and cost analysis.

Updated March 2026

Cost Simulator

Claude Sonnet 4.5 Cost
$6.00
Claude Opus 4.6 Cost
$10.00
Claude Sonnet 4.5 is 40% cheaper
FeatureClaude Sonnet 4.5Claude Opus 4.6
ProviderAnthropicAnthropic
Input Price (1M)$3.00$5.00
Output Price (1M)$15.00$25.00
Context Window200,0001,000,000

Verdict

Claude Sonnet 4.5 costs $3.00 per 1M input tokens and $15.00 per 1M output tokens. Claude Opus 4.6 costs $5.00 per 1M input tokens and $25.00 per 1M output tokens. Claude Sonnet 4.5 is 40% cheaper on input tokens than Claude Opus 4.6. For output tokens, Claude Sonnet 4.5 is the more affordable option at $15.00/1M vs $25.00.

On context window, Claude Opus 4.6 supports 1,000,000 tokens — meaning it can fit more conversation history, documents, or code in a single request. This matters for RAG pipelines, long document analysis, and agentic workflows where context builds up over many turns.

When to choose Claude Sonnet 4.5

  • ✓ You need the lowest input token cost ($ 3.00/1M)
  • ✓ Your workload is output-heavy — Claude Sonnet 4.5 generates text cheaper
  • ✓ You are already integrated with Anthropic

When to choose Claude Opus 4.6

  • ✓ You need a larger context window (1,000,000 tokens)
  • ✓ You are already integrated with Anthropic

Use the calculator above to simulate your specific workload and find the exact break-even point. For most applications, the cheapest model is the one that minimises your total monthly bill given your input-to-output token ratio.