Model
Model explorer

Claude Sonnet 4.6

CLOSED
Anthropic · Claude 4 family · released Feb 17, 2026

CONFIRMED REAL — this is not a mix-up. Model id claude-sonnet-4-6. Direct predecessor to Claude Sonnet 5, sitting between Sonnet 4.5 and Sonnet 5 in the lineage; the corpus is missing it even though it already has both Opus 4.6 (2026-02-05) and Sonnet 5 (2026-06-30). Introduced 1M-token context (beta) and adaptive thinking for the Sonnet line.

ReasoningCodingVisionFunction callingTool useAgentic
2437.8
Elo · rank #25
Parameters
Undisclosed
Active params
—
Context
1M tokens
Architecture
Dense transformer, architecture undisclosed
License
Proprietary
Languages
—
API price (in/out)
$3 / $15
Modalities
text · vision
Benchmark results
Bar shows position within the tracked field; marker = field best
Agents' Last ExamAgents32.0%#10
best: GPT-5.6 · 52.7%
AIMEMath95.6%#12
best: GPT-5.2 · 100.0%
ARC-AGI-2Reasoning58.3%#10
best: GPT-5.6 · 92.5%
BrowseCompAgents74.0%#21
best: Kimi K3 · 91.2%
CharXivVision72.4%#21
best: Muse Spark 1.1 (xhigh) · 88.4%
GDPval-AAAgents1633#7
best: Claude Fable 5 · 1932
GPQA DiamondReasoning89.9%#29
best: GPT-5.6 · 94.6%
Humanity's Last ExamReasoning49.0%#8
best: Claude Sonnet 5 · 57.4%
LiveCodeBenchCoding82.1%#39
best: DeepSeek-V4-Pro (Think Max) · 93.5%
MMLU-ProKnowledge87.3%#10
best: Claude Fable 5 · 91.5%
MMMLUKnowledge89.3%#9
best: Gemini 3.1 Pro · 92.6%
MMMU-ProVision83.6%#3
best: Claude Opus 4.7 · 85.5%
OSWorld-VerifiedAgents72.5%#13
best: Claude Fable 5 · 85.0%
SWE-bench ProCoding58.1%#14
best: Claude Fable 5 · 80.0%
SWE-bench VerifiedCoding79.6%#19
best: Claude Fable 5 · 95.0%
τ²-Bench RetailAgents91.7%#1
best: this model · 91.7%
τ²-Bench TelecomAgents97.9%#10
best: Claude Opus 4.6 · 99.3%
Terminal-Bench 2.0Coding67.0%#20
best: GPT-5.6 · 88.8%
Run it locally
Closed weights — available via API only. No local deployment.
Input / M tok
$3
Output / M tok
$15
Claude 4 family
Elo progression across releases
Claude Opus 4May 20251702.9Claude Sonnet 4May 20251594.8Claude Opus 4.1Aug 20251760.6Claude Sonnet 4.5Sep 20251976.7Claude Haiku 4.5Oct 20251590.8Claude Opus 4.5Nov 20252274.5Claude Opus 4.5 (High)Nov 20252301.0Claude Opus 4.5 (Medium)Nov 20252283.3Claude Opus 4.6Feb 20262459.4Claude Sonnet 4.6Feb 20262437.8Claude Opus 4.7Apr 20262702.0Claude Opus 4.8May 20262794.3
Resources
DOCShttps://platform.claude.com/docs/en/about-claude/models/overviewAPIAvailable via Anthropic API
API price $3/$15 · each benchmark row carries its own source badge (see methodology)