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AnthropicClaude 4 familyLegacyReasoning modelReleased 17 Feb 2026

Claude Sonnet 4.6

Legacy Sonnet; migrate to claude-sonnet-5-5.

Model idclaude-sonnet-4-6

Price$3 in, $15 out per 1M tokens

Checked29 September 2026

Knows up to August 2025

2,002events after its cutoff

87 historic, 461 major. 439 days of news.

It launched on 17 February 2026, already missing 73 of them. Coverage before 2026 is thin (80 entries for 2025), so this count is a floor.

Five things it has never heard of

Its cutoff, August 2025, is before this chart starts: every mark here is news it has never seen.

How to call it

7 ways to use Claude Sonnet 4.6, with the model id each provider expects.

Providers, model ids, endpoints and docs for Claude Sonnet 4.6
ProviderModel idEndpointDocs
Anthropic API (Claude API) claude-sonnet-4-6 https://api.anthropic.com/v1/messages platform.claude.com
AWS Bedrock (InvokeModel) anthropic.claude-sonnet-4-6 platform.claude.com
Google Cloud Vertex AI claude-sonnet-4-6 platform.claude.com
Microsoft Foundry (Azure) claude-sonnet-4-6 platform.claude.com
Claude Platform on AWS claude-sonnet-4-6 platform.claude.com
OpenRouter anthropic/claude-sonnet-4.6 openrouter.ai
Web app claude.ai

Pricing

Prices for Claude Sonnet 4.6
Input$3 per 1M tokens
Output$15 per 1M tokens
Cache read$0.30 per 1M tokens

As published: “per 1M tokens (USD); Batch API 50% off”.

Source: platform.claude.com, checked 29 September 2026.

Specs

Input
Text, images and PDF
Output
Text
Context window
1,000,000 tokens
Max output
128,000 tokens
Open weights
No
Licence
Proprietary
Training cutoff
August 2025
Released
17 February 2026
Status
Legacy
Type
Reasoning model

What stands out

What its maker marketed at launch, and what people found later, each with its source.

  • Human-level computer use on common tasks

    Anthropic cites human-level performance on tasks such as navigating complex spreadsheets and multi-step web forms (OSWorld).

    Source: anthropic.com

  • Beats previous Opus in user preference

    Users preferred it to Opus 4.5 59% of the time on coding, citing less overengineering.

    Source: anthropic.com

  • 1M context for Sonnet 4.6

    1M-token context window (beta at launch).

    Source: anthropic.com

Four assistants, one scale

Claude Sonnet 4.6 is added as a fifth row. Each row runs from what the model knows (graphite) through the months between its cutoff and its launch (hatched) to today (pink).

  1. GPT-6 Astra 271 at launch, 1,863 today
  2. Claude Opus 5.5 372 at launch, 1,795 today
  3. Gemini 4 Hydrogen 1,863 at launch, 1,889 today
  4. Grok 4.7 387 at launch, 1,829 today
  5. Claude Sonnet 4.6 73 at launch, 2,002 today
Show as a table
ModelCutoffReleasedMissing at launchMissing today
GPT-6 AstraApril 20263 September 20262711,863
Claude Opus 5.5June 202622 September 20263721,795
Gemini 4 HydrogenMarch 202612 November 20261,8631,889
Grok 4.7May 202621 September 20263871,829
Claude Sonnet 4.6August 202517 February 2026732,002

Notes

Last model on the older tokenizer. Adaptive thinking (budget_tokens deprecated). Training data cutoff Jan 2026. Bedrock via InvokeModel. Retirement not sooner than 2027-02-17.

curl https://api.anthropic.com/v1/messages \
 -H "x-api-key: $ANTHROPIC_API_KEY" -H "anthropic-version: 2023-06-01" -H "content-type: application/json" \
 -d '{"model":"claude-sonnet-4-6","max_tokens":16000,"messages":[{"role":"user","content":"Hello"}]}'

Sources: