Claude Opus 4.6 vs Claude Sonnet 4.6

API pricing, benchmark indices and specs — updated 19 October 2026.

anthropic · A · API-only
Input / 1M
$5.00
Output / 1M
$25.00
AA index
31.9
proprietary · 1M context
anthropic · B · API-only
Input / 1M
$3.00
Output / 1M
$15.00
AA index
30.1
proprietary · 1M context

Specification comparison

Differences are highlighted; identical values are muted.

Specification Claude Opus 4.6 Claude Sonnet 4.6
Deployment API-only (closed weights) API-only (closed weights)
Parameters n/a — API-only n/a — API-only
Architecture n/a — API-only n/a — API-only
Context length 1,000,000 1,000,000
Licence Proprietary Proprietary
Commercial use Per API terms Per API terms
Languages n/a — API-only n/a — API-only
Downloads 30d n/a — API-only n/a — API-only
Downloads all time n/a — API-only n/a — API-only
Quantizations on the Hub n/a — API-only n/a — API-only
Gated n/a — API-only n/a — API-only
First seen on the Hub n/a — API-only n/a — API-only
API input price / 1M tokens $5.00 $3.00
API output price / 1M tokens $25.00 $15.00
Est. cost per 1M input + 1M output tokens $30.00 $18.00
Cached input / 1M tokens $0.50 $0.30
AA Intelligence Index 31.9 30.1
AA Coding Index — 63
AA Agentic Index — 31.8
Max output tokens 128,000 128,000
API providers 5 5
Tool calling Yes Yes
Reasoning mode Yes Yes

API cost

Estimated cost of 1M input + 1M output tokens via OpenRouter

Claude Opus 4.6 $30.00
Claude Sonnet 4.6 $18.00

Claude Sonnet 4.6 is 1.7× cheaper at list price.

Adjacent comparisons