How much does the Claude Sonnet 4.6 API cost?

Claude Sonnet 4.6 costs $3 per million input tokens and $15 per million output tokens, with cached input at $0.3 per million. A workload of 10M input and 1.5M output tokens per month costs about $52.50.

What is the context window of Claude Sonnet 4.6?

Claude Sonnet 4.6 supports a context window of 1,000,000 tokens (1M), with up to 64K output tokens per response.

Is Claude Sonnet 4.6 open source?

No — Claude Sonnet 4.6 is a proprietary model available through Anthropic's API and partner platforms.

What are the best alternatives to Claude Sonnet 4.6?

The closest alternatives by overall capability are Qwen3-Max, GPT-5.5, Gemini 3 Pro, Gemini 2.5 Pro. See the comparison pages for detailed head-to-head breakdowns.

Claude Sonnet 4.6

Name: Claude Sonnet 4.6
Price: 3 USD
Author: Anthropic

Anthropic·Apr 2026reasoningproprietary

Claude Sonnet 4.6 is the balanced model in Anthropic's 2026 lineup — the one most production Claude workloads actually run on. It delivers a large share of Opus 4.8's capability at 60% of the price, supports the 1M-token context window, and notably beats Opus on the Finance Agent benchmark, making it a favorite for tool-heavy business automation. For teams choosing between Claude tiers, Sonnet 4.6 is the default and Opus the escalation path.

Benchmark results

SWE-bench VerifiedCoding · #9 of 33~79.6%

Where it shines

Best price-to-capability ratio in the Claude lineup
Leads Opus on finance/business agent tasks
1M context with 90% cache discount for agent loops

Alternatives to Claude Sonnet 4.6

Qwen3-Max

Alibaba's trillion-parameter API flagship — frontier-adjacent quality with strong agentic tool use at mid-tier prices.

GPT-5.5

OpenAI's flagship reasoning model with a 1M-token context window, built for hard coding, science and long-horizon agentic work.

Gemini 3 Pro

Google's November 2025 frontier breakout — 91.9% GPQA Diamond and 37.5% HLE made it the reasoning leader of its generation.

Gemini 2.5 Pro

Google's 2025 workhorse flagship — first mainstream thinking model with a 1M context, still widely deployed.

Frequently asked questions

How much does the Claude Sonnet 4.6 API cost?: Claude Sonnet 4.6 costs $3 per million input tokens and $15 per million output tokens, with cached input at $0.3 per million. A workload of 10M input and 1.5M output tokens per month costs about $52.50.
What is the context window of Claude Sonnet 4.6?: Claude Sonnet 4.6 supports a context window of 1,000,000 tokens (1M), with up to 64K output tokens per response.
Is Claude Sonnet 4.6 open source?: No — Claude Sonnet 4.6 is a proprietary model available through Anthropic's API and partner platforms.
What are the best alternatives to Claude Sonnet 4.6?: The closest alternatives by overall capability are Qwen3-Max, GPT-5.5, Gemini 3 Pro, Gemini 2.5 Pro. See the comparison pages for detailed head-to-head breakdowns.