Model
Claude Opus 4.5
Claude Opus 4.5, released on 24 November 2025, cost a third as much as Opus 4.1 per token and introduced an effort parameter that lets developers trade capability for time and cost. Claude Opus 4.6 succeeded it.
Status AvailableModality Text, ImageContext (K tokens) 200 Era Generative AI for everyone
- License
- Proprietary
- Access
- API, App, Enterprise
- Release date
- Developer
- Anthropic
What it is
Claude Opus 4.5 is a large language model developed by Anthropic and released on 24 November 2025 under the API identifier claude-opus-4-5-20251101. It was made available through the Claude API, the Claude apps and all three major cloud platforms.[1][2]
Origins
The model followed Claude Opus 4.1. Anthropic priced it at $5 per million input tokens and $25 per million output tokens, one third of the $15 and $75 charged for Opus 4.1.[1][4] The model's training data ran to May 2025, and Wikipedia notes that its main gains were in coding and spreadsheet tasks.[3]
Main features
Anthropic said the model was state-of-the-art on SWE-bench Verified, a coding benchmark. On SWE-bench Multilingual, which tests software engineering across programming languages, it led in seven of eight languages. On Aider Polyglot, another coding benchmark, it improved 10.6% over Sonnet 4.5.[1]
Anthropic also reported that on its own take-home engineering exam, the model scored higher than any human candidate within the two-hour limit. This result used parallel test-time compute, which means running several attempts at once and combining them.[1]
The model introduced an effort parameter. Developers can set it to trade capability against speed, time and cost.[1]
Anthropic called it its “most robustly aligned model”. On a Gray Swan benchmark, it was harder to trick with prompt injection, in which hidden instructions in content try to hijack a model, than any other frontier model the company had tested.[1]
On the product side, the release shipped with Plan Mode and a desktop app for Claude Code, and automatic summarisation of earlier context so that long Claude conversations no longer hit a limit. Claude for Chrome was made available to all Max users, and Claude for Excel was made available more widely.[1]
Opus-specific usage caps were removed for Claude and Claude Code users with Opus 4.5 access.[1]
Its place in development
Claude Opus 4.6 succeeded the model on 5 February 2026. Anthropic has said its retirement is not sooner than 24 November 2026.[2][3]
Version history
20-
2023
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Mar 14, 2023
Claude (March 2023)
Claude is the AI assistant Anthropic announced on 14 March 2023, its first publicly available assistant. It was built around training AI to be helpful, honest and harmless, and it started the Claude model line.
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Jul 11, 2023
Claude 2
Claude 2 is the second major version of Anthropic's assistant model, released on 11 July 2023 with better performance and longer responses. It was the first Claude model open to the general public.
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Nov 21, 2023
Claude 2.1
Claude 2.1, released on 21 November 2023, doubled the context window to 200,000 tokens and cut false statements by half compared with Claude 2.0. It added tool use and system prompts.
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Mar 14, 2023
Claude (March 2023)
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2024
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Mar 4, 2024
Claude 3 Opus
Claude 3 Opus, announced on 4 March 2024, was the most capable model in the Claude 3 family. It added vision and launched with a 200K-token context window and a Needle In A Haystack recall above 99%.
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Mar 4, 2024
Claude 3 Sonnet
Claude 3 Sonnet was the middle model of Anthropic's Claude 3 family, announced on 4 March 2024. It powered the free tier of claude.ai, offered a 200K-token context window, and was retired on 21 July 2025.
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Jun 20, 2024
Claude 3.5 Sonnet
Claude 3.5 Sonnet, released on 20 June 2024, was the first model of the Claude 3.5 family. It ran twice as fast as Claude 3 Opus at the mid-tier price and powered the new Artifacts and Projects features.
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Oct 22, 2024
Claude 3.5 Sonnet (October 2024 upgrade)
The upgraded Claude 3.5 Sonnet, announced on 22 October 2024, raised coding and agentic scores and introduced computer use in public beta, the first such offer from a frontier AI model.
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Mar 4, 2024
Claude 3 Opus
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2025
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Feb 24, 2025
Claude 3.7 Sonnet
Claude 3.7 Sonnet, released on 24 February 2025, was described by Anthropic as the first hybrid reasoning model on the market, able to answer quickly or think step by step at length. It launched with Claude Code.
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May 22, 2025
Claude 4 (Claude Opus 4 and Claude Sonnet 4)
Claude Opus 4 and Claude Sonnet 4, announced on 22 May 2025, were hybrid models with extended thinking. Anthropic called Opus 4 the best coding model in the world, and Claude Code became generally available the same day.
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Aug 5, 2025
Claude Opus 4.1
Claude Opus 4.1, released on 5 August 2025, upgraded Claude Opus 4 for agentic tasks, real-world coding and reasoning, at the same price. Anthropic later succeeded it with Claude Opus 4.5.
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Sep 29, 2025
Claude Sonnet 4.5
Claude Sonnet 4.5, released on 29 September 2025, was a drop-in replacement for Sonnet 4 at the same price. Anthropic reported that it could stay focused on complex tasks for more than 30 hours.
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Nov 24, 2025
Claude Opus 4.5 · This page
Claude Opus 4.5, released on 24 November 2025, cost a third as much as Opus 4.1 per token and introduced an effort parameter that lets developers trade capability for time and cost. Claude Opus 4.6 succeeded it.
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Feb 24, 2025
Claude 3.7 Sonnet
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2026
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Feb 5, 2026
Claude Opus 4.6
Released on 5 February 2026, Claude Opus 4.6 was an upgrade to Anthropic's smartest model. It was the first Opus-class model with a 1M-token context window, in beta at launch, and it introduced agent teams in Claude Code.
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Feb 17, 2026
Claude Sonnet 4.6
Released on 17 February 2026 with a 1M-token context window in beta, Claude Sonnet 4.6 kept the price of Sonnet 4.5 and became the default model for Free and Pro users on claude.ai.
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Apr 16, 2026
Claude Opus 4.7
Released on 16 April 2026 at the same price as Opus 4.6, Claude Opus 4.7 added an xhigh effort level and accepted much larger images. It was the first model to test automatic blocking of high-risk cybersecurity requests.
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May 28, 2026
Claude Opus 4.8
Released on 28 May 2026 at the same price as Opus 4.7, Claude Opus 4.8 added a fast mode at 2.5 times the speed, with fewer unnoticed flaws in its own code. Anthropic called it a modest but tangible improvement.
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Jun 30, 2026
Claude Sonnet 5
Claude Sonnet 5, released on 30 June 2026, is Anthropic's most agentic Sonnet model. It can make plans, use browsers and terminals, and run autonomously, at an introductory price of $2 and $10 per million tokens.
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Jul 24, 2026
Claude Opus 5
Claude Opus 5, released on 24 July 2026 at $5 and $25 per million tokens, is Anthropic's most aligned model to date and its most capable generally available model for scientific research.
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Sep 22, 2026
Claude Opus 5.5
Claude Opus 5.5, released on 22 September 2026, is the first model in Anthropic's Claude 5.5 family. Anthropic said it performs at the level of Fable 5.1 on most work, at about 40% lower cost than Opus 5.
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Sep 28, 2026
Claude Sonnet 5.5
Claude Sonnet 5.5, released on 28 September 2026, is the second model in the Claude 5.5 family and Anthropic's fastest Sonnet to date. It costs $2 and $10 per million tokens, with cache reads halved in October 2026.
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Feb 5, 2026
Claude Opus 4.6
20251
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ReleaseAnthropic releases Claude Opus 4.5
On 24 November 2025 Anthropic released Claude Opus 4.5 at $5 and $25 per million tokens, a third of the previous Opus price, with a new effort parameter for trading capability against cost.
Developed by1
Succeeded by1
Successor of1
Notes and sources
- Introducing Claude Opus 4.5https://www.anthropic.com/news/claude-opus-4-5
- Model deprecationshttps://platform.claude.com/docs/en/about-claude/model-deprecations
- Claude (language model)https://en.wikipedia.org/wiki/Claude_(language_model)
- Pricinghttps://platform.claude.com/docs/en/about-claude/pricing
Cite this page: Claude Opus 4.5. TellWorld, https://www.tellworld.net/models/claude-opus-4-5. Updated 2026-11-08