On August 5, 2025, Anthropic released Claude Opus 4.1, which they described as a drop-in replacement for Opus 4.
The version number tells you what you need to know. Unlike GPT-5, this is an incremental update. The model has the same 200,000 token context window as the previous model, with 32,000 output tokens, while it gains an expanded thinking capability which can now use up to 64,000 tokens for complex reasoning tasks.
You can get it through Overchat AI, Claude Pro, Max, Team, and Enterprise subscriptions, as well as the Anthropic API with the model string claude-opus-4-1-20250805, Amazon Bedrock, and Google Cloud's Vertex AI.
For developers using Claude Code, the command-line integration provides direct terminal access to the model's capabilities. This is important for engineers who want to use AI without leaving the development environment.
The performance gains over Opus 4, which already was one of the leading AI models, are modest, at least on paper.
Here's how the performance changed between Claude Opus 4 and 4.1:
It's interesting to note that some real-world feedback indicates a higher performance gain than the benchmarks.
Windsurf's internal testing showed that the improvement from Opus 4 to 4.1 is equivalent to a full standard deviation gain on their junior developer benchmark. That's the same level of improvement they saw between Sonnet 3.7 and Sonnet 4.
This raises the question: is the model really that much better? It seems that the biggest improvements in performance are in advanced coding tasks and agentic reasoning, but you'll have to test it for yourself to see if it has improved in terms of your specific use case.
The most impressive feature is the ability to reorganize code into multiple files. GitHub specifically noted "particularly notable performance gains" in this area, while Rakuten Group reported that the model excels at pinpointing exact corrections within large codebases without making unnecessary adjustments or introducing new bugs.
In their tests, Rakuten found that tasks were completed 50% faster.
The model is now very precise and follows instructions well. Cursor says that Opus 4.1, along with Sonnet 4, shows the best coding skills and a better understanding of complex code. This fundamentally changes how their agent works. The model understands when not to touch the code. This is a critical skill that separates useful tools from those that create more problems than they solve.
Along those lines, the creative writing has also improved and now should feel more natural.
Anthropic calls this "rich, deep character." The output should feel less robotic, but it's still clearly AI-generated, but should have less awkward phrasing or repetitive patterns.
The prices are the same as they were for Opus 4:
This makes it one of the most expensive models available.
It usually costs $7-8 to solve complex coding tasks. If you use the model a lot, you might have to pay up to $2,500 per month.
If you want to try Opus 4.1 without spending too much, you can chat with this model on Overchat AI for $4.99 per week.
Anthropic uses Claude Opus 4.1, which meets their AI Safety Level 3 (ASL-3) Standard. The safety metrics show significant improvements without making the product harder to use. The model gets a 98.76% refusal rate for requests that violate the rules, up from 97.27% in Opus 4, while keeping only a 0.08% refusal rate for requests that are not harmful.
There's a 25% decrease in cooperation when it comes to really bad misuse compared to the previous version.
The safety improvements don't reduce the capabilities. This is not the cautious approach seen in earlier safety-focused releases.
The Claude Opus 4.1 seems like a good release, but let's talk about the possible problems.
First of all, some people say that the model is "too creative for normal code." This means that it comes up with overly clever solutions to simpler problems, instead of following established patterns. This can make it harder to maintain the code it generates.
Secondly, the model is pretty slow. GPT-5 will have it beat for answering simple questions, making it the better choice when you need quick answers.
Lastly, the high cost means you should only use it in situations where the better performance is worth the expense. At $75 per million output tokens, you need to be careful about when to use this model instead of more affordable options.
Claude Opus 4.1 is Anthropic's latest AI model, released August 5, 2025, as a drop-in replacement for Opus 4. It's an incremental update that delivers better performance at the same price, with particular improvements in coding and autonomous task handling.
Use Claude Opus 4.1 for complex, multi-step problems that require careful analysis, such as:
For simple queries or when speed is important, cheaper and faster models like Sonnet 4 or GPT-5 may be better.
It costs $15 for every million input tokens, and $75 for every million output tokens. Batch processing offers 50% discounts. In practice, complex coding tasks cost between $7 and $8 each. With heavy development workflows, the cost could reach $2,500 per month.
Claude Opus 4.1 is available through Overchat AI and Claude Pro, as well as through the Anthropic API (model string: claude-opus-4-1-20250805), Amazon Bedrock, Google Cloud's Vertex AI, and Claude Code for terminal-based workflows.
The biggest improvements are in coding (a 2% increase on the SWE-bench), Terminal-Bench performance, and mathematical reasoning. Rakuten tested this model in the real world and found that tasks were completed 50% faster.
The branding is perfect for Claude Opus 4.1. It's a small update to a model that's already very popular, especially with businesses.
Most Benchmarks saw improvements of about one to two percentage points, but some users have reported seeing much bigger improvements in how well it works in the real world. As the saying goes, "Underpromise and overdeliver." This is how Antrophic has been building their models, and it's definitely the case here.
But according to Anthropic, there will be "significant improvements" soon — maybe a Claude 5? It will be very interesting to see how that future release compares to GPT-5. For now, we have another new model that is just as good!
