Released June 30, 2026. Default model for Free and Pro claude.ai plans. Promo pricing $2/$10 per 1M through Aug 31, 2026, then $3/$15. 128K max output, Jan 2026 knowledge cutoff.
72.7% on SWE-bench Verified (vs Sonnet 4.6's 62.3% on the same eval) with launch promo pricing of $2/$10 through August 31, 2026
78.5% OSWorld-Verified computer use and 46.8% on Humanity's Last Exam with tools
1M-token context in the fast Sonnet latency class — Opus-adjacent quality without Opus latency
Weaknesses
Clearly behind Opus 5 and Fable 5 on the hardest reasoning and long-horizon agent tasks
Updated tokenizer produces ~1.0–1.35x more tokens for the same text, so effective cost runs above sticker price
Real-world use cases
What people actually use Claude Sonnet 5 for.
Production agent loops that plan, call tools, verify output, and finish multi-step tasks
High-volume coding assistance at one-fifth of Opus 5's price
Computer-use automation — 78.5% on OSWorld-Verified
How Claude Sonnet 5 compares
The nearest models people weigh against it, and what actually separates them.
vs Claude 3.5 Sonnet — Against Claude 3.5 Sonnet (Anthropic), Claude Sonnet 5 runs about 67% cheaper per token, takes 5x the context and answers faster. Take Claude Sonnet 5 unless you specifically need what Claude 3.5 Sonnet does better.
vs Claude Fable 5 — Against Claude Fable 5 (Anthropic), Claude Sonnet 5 runs about 80% cheaper per token and answers faster. Take Claude Sonnet 5 unless you specifically need what Claude Fable 5 does better.
vs Claude Fable 5.1 — Against Claude Fable 5.1 (Anthropic), Claude Sonnet 5 runs about 80% cheaper per token and answers faster. Take Claude Sonnet 5 unless you specifically need what Claude Fable 5.1 does better.
Price History
Claude Sonnet 5 pricing over time
↑100% since Aug 7
38 data points · tracked daily since Aug 7, 2026
Ready to try it?
Start using Claude Sonnet 5
High-volume agentic workloads and production apps at mid-tier pricing. Start free — no card required.
Claude 3.5 Sonnet is Anthropic's mid-cycle flagship model, balancing strong reasoning, coding, and instruction-following with a 200K context window. It sits between Haiku and Opus in Anthropic's lineup, offering near-flagship quality at a lower cost than top-tier models.
Verdict
One of the best models for coding and complex instruction-following, but its premium pricing demands premium use cases.
Quality score
81%
Pricing
$6.00/1M in
$30.00/1M out
Speed
Balanced
3/5 speed
Context
200k tokens
Pricing at $6 input / $30 output per million tokens is significantly higher than GPT-4o ($2.50/$10). Best accessed via Anthropic API or Amazon Bedrock. Claude 3.5 Sonnet (October 2024 version) supersedes the June 2024 release with improved performance.
Anthropic's new Mythos-class flagship and the most capable coding model anyone can use — 80.3% SWE-Bench Pro, an 11-point jump over Opus 4.8. 1M context, 128K output, native parallel subagents. Released June 9, 2026.
Verdict
New global #1 — 80.3% SWE-Bench Pro, the most capable model generally available.
Quality score
98%
Pricing
$10.00/1M in
$50.00/1M out
Speed
Deliberate
2/5 speed
Context
1M tokens
Launched June 9, 2026 as the public, Mythos-class release. Available on the Claude API, Microsoft Foundry, and Google Vertex AI. Free for all users until June 22, 2026. Same underlying model as Claude Mythos 5, with safeguards that block specific high-risk cyber responses.
Coding leaderSWE-Bench Pro #1Mythos-classParallel subagentsAgenticLong contextPremiumNew
Best for
The hardest coding tasks, autonomous multi-step agents, and frontier-grade reasoning
Anthropic's September 1, 2026 frontier release and the new capability ceiling for coding, agents, and scientific work. Base pricing is unchanged at $10/$50, but cache reads dropped 75% to $0.25/1M — roughly 25% cheaper on typical workloads and up to 45% cheaper on agentic ones. 1M context, 128K output, adaptive thinking always on.
Verdict
New frontier leader — better than Fable 5 on every published benchmark, and cheaper to run.
Quality score
98%
Pricing
$10.00/1M in
$50.00/1M out
Speed
Deliberate
2/5 speed
Context
1M tokens
Released September 1, 2026 alongside Claude Mythos 5.1, the first update to the Mythos-class line since Fable 5 on June 9. API ID claude-fable-5-1; generally available on the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry. Published launch numbers (Fable 5.1 / Fable 5 / Opus 5 / GPT-5.6 Sol): Terminal-Bench-Science 0.1 52.6 / 24.7 / 29.0 / 22.4; Terminal-Bench 4.0 55.8 / 42.0 / 52.3 / 37.3; CursorBench 3.2.0 73.4 / 70.5 / 70.0 / 67.2; AutomationBench 31.4 / 17.1 / 26.9 / 19.6; OSWorld 2.0 strict 41.7 / 36.1 / 39.6; Humanity's Last Exam (no tools) 60.9 / 57.8 / 56.6; GDPval-AA v2 1853 / 1723 / 1824 / 1711. GDPval-AA v2 is rescaled from the v1 numbers quoted on the Fable 5 page and is not directly comparable to them.
Claude Sonnet 5 costs $2 per million input tokens and $10 per million output tokens on the API, with cached input at $0.2 per million. A month of 10M input and 2M output tokens runs about $40.00 at list price, before any batch or caching discounts.
What is the context window of Claude Sonnet 5?
Claude Sonnet 5 has a 1M tokens context window, with up to 128k tokens of output per response. That is the total of prompt plus response the model can hold in one request.
What is the knowledge cutoff of Claude Sonnet 5?
Claude Sonnet 5's training data runs through January 31, 2026, and the model was released on June 29, 2026. For anything after that date it needs web search or documents in the prompt.
What is Claude Sonnet 5 best for?
Claude Sonnet 5 is best for high-volume agentic workloads and production apps at mid-tier pricing. It is a strong fit when that workflow matters more than the tradeoffs around premium pricing and fast speed.
When should I avoid Claude Sonnet 5?
You need the absolute top coding ceiling — Opus 5 leads SWE-bench Verified by over 20 points.
What is a cheaper alternative to Claude Sonnet 5?
GPT-5.1-Codex-Max (OpenAI) at $1.25/1M/1M input against Claude Sonnet 5's $2.00/1M/1M — roughly 6% less per token all in. The strongest choice for serious software engineering work, provided you can absorb the output-side pricing. Compare it first if Claude Sonnet 5's pricing is the thing stopping you.
What is a faster alternative to Claude Sonnet 5?
Claude 3.5 Sonnet — balanced against Claude Sonnet 5's fast, with 200k tokens of context. Worth the swap when response time is what your users notice rather than the last few points of reasoning depth.
Newsletter
Get notified when Claude Sonnet 5 pricing changes
We track pricing daily. When this model drops or spikes, you'll know first.
No spam. Useful updates only. Affiliate disclosures always clearly labeled.