Claude Opus 5.5 is Anthropic’s newest Opus model for advanced coding, long-running agents and professional knowledge work. Announced on September 22, 2026, it is positioned as the strongest Opus release so far while reducing the cost of typical token-billed workloads compared with Claude Opus 5.
This guide explains what changed in Claude Opus 5.5, how much it costs, where it is available, what Anthropic says about its coding and agent capabilities, and when it makes sense to choose it over less expensive models.
What is Claude Opus 5.5?
Claude Opus 5.5 is the first model in Anthropic’s Claude 5.5 family. Anthropic describes it as its most capable Opus model for coding, agents and knowledge work. The company says it performs at the level of Claude Fable 5.1 on most work while costing about 40% less to run than Opus 5 for typical workloads billed by token.
For developers, the API model name is claude-opus-5-5. Anthropic also makes the model available through Claude, Claude Code and major cloud platforms.
- Release date: September 22, 2026
- API model:
claude-opus-5-5 - Core strengths: advanced coding, agentic workflows, knowledge work, vision and computer use
- Standard API price: $4 / million input tokens and $20 / million output tokens
- Cache reads: $0.20 / million tokens
- Fast mode: up to 2.5x faster, priced at $8 input / $40 output per million tokens
What changed from Claude Opus 5?
The most important change is not simply a benchmark bump. Anthropic is presenting Opus 5.5 as a more efficient model for real, long-running work. That matters because coding agents and enterprise workflows can consume a large number of tokens over many steps.
Anthropic says Opus 5.5 costs 20% less per input and output token than Opus 5, while cache reads are 60% cheaper. Because it can also use fewer tokens on some tasks, Anthropic estimates that typical token-billed work can cost about 40% less overall.
The model is also designed to communicate more clearly, follow writing rules more reliably and stay focused during long sessions. Those improvements are especially relevant in production coding, document creation, financial analysis and multi-tool agent workflows.
Claude Opus 5.5 pricing
| Mode | Input | Output | Notes |
|---|---|---|---|
| Standard | $4 / 1M tokens | $20 / 1M tokens | Default Opus 5.5 API pricing |
| Cache reads | $0.20 / 1M tokens | — | Important for long-running agent workflows |
| Fast mode | $8 / 1M tokens | $40 / 1M tokens | Up to 2.5x faster |
| US-only inference | 1.1x standard input/output pricing | For workloads requiring US-only processing | |
Pricing can change, so developers should always check Anthropic’s current pricing documentation before estimating production costs.
Why Opus 5.5 matters for coding
Anthropic calls Opus 5.5 its strongest Opus model for agentic coding. The model is intended for tasks that go beyond autocomplete or short code generation: large codebases, feature implementation, debugging, refactoring, code review and long-running engineering tasks.
The key idea is persistence. A coding model becomes much more valuable when it can investigate a repository, identify the root cause of a problem, make changes, run checks, revise its approach and explain what changed without needing constant human intervention.
That puts Opus 5.5 in direct competition with the newest generation of coding-oriented reasoning models. If you are comparing coding agents more broadly, Vynula’s Claude Code vs Codex vs Cursor guide and best AI coding agents guide provide more context.
Agentic workflows and long-running tasks
Opus 5.5 is also aimed at AI agents that need to plan, use tools, coordinate subagents and continue working over extended periods. Anthropic says the model can orchestrate complex multi-tool tasks, use memory across sessions and report what it did in a clearer way.
This is a significant shift from the older “chatbot” model of AI. In an agentic workflow, the model may need to inspect files, call APIs, use a browser or computer interface, generate documents, validate results and decide what to do next.
For companies building internal agents, the practical question is not whether a model can answer a difficult prompt once. It is whether it can complete a long sequence of dependent tasks reliably enough to justify the cost.
Knowledge work and enterprise use
Anthropic positions Opus 5.5 as an enterprise daily driver for complex professional work. Its highlighted use cases include document creation, spreadsheets, presentations, financial analysis and workflows that require the model to maintain context across many steps.
That makes the model relevant to analysts, consultants, engineers, operations teams and other users who need more than fast conversational responses. The higher price compared with lightweight models can make sense when the task itself is expensive, complex or time-consuming for a person.
Vision and computer use
Anthropic also describes Opus 5.5 as its strongest Opus model for vision and computer use. It is designed to interpret dense documents, charts, screenshots and diagrams while reasoning across multi-step tasks that span applications.
This capability matters for agents that need to interact with existing software rather than only APIs. A model that can understand a screen, decide what action is appropriate and continue across several applications can automate workflows that traditional integrations do not cover easily.
Claude Opus 5.5 benchmarks: how to read the claims
Anthropic reports improvements across coding, automation and professional-work evaluations, but benchmark results should be treated as one part of the decision rather than a universal ranking. Scores depend on the evaluation harness, effort setting, tool access, safeguards and the exact version of the benchmark.
The more useful test for a team is to run Opus 5.5 against its own workload: the same repositories, documents, agent tools and acceptance criteria used in production. Measure task completion, correction rate, latency and total cost—not only raw benchmark scores.
Claude Opus 5.5 vs GPT-6 Sol
Claude Opus 5.5 and OpenAI’s GPT-6 Sol were both released in September 2026 and both target serious coding and agentic workloads, but their pricing structures differ substantially.
| Model | Input price | Output price | Positioning |
|---|---|---|---|
| Claude Opus 5.5 | $4 / 1M | $20 / 1M | Anthropic’s premium Opus model for coding, agents and knowledge work |
| GPT-6 Sol | $2 / 1M | $10 / 1M | OpenAI reasoning model for complex coding and agentic workflows |
Those API prices do not tell you which model is cheaper for a real task. A model that completes work in fewer steps or uses fewer output tokens can have a lower total cost even if its token price is higher. Teams should benchmark both models on representative workflows before standardizing.
For more detail on OpenAI’s current model lineup, see Vynula’s GPT-6 Sol vs GPT-6 Luna comparison, ChatGPT model selection guide and ChatGPT models explained.
Who should use Claude Opus 5.5?
Opus 5.5 makes the most sense when task quality and autonomy are more important than minimizing the price of every token. Typical candidates include software teams working on large repositories, companies building long-running AI agents, analysts processing complex documents and teams automating high-value professional workflows.
For simple classification, summarization, routine extraction or high-volume low-complexity requests, a smaller model may still be more economical. Premium models are most valuable when their additional reasoning or reliability actually changes the outcome.
Where is Claude Opus 5.5 available?
Anthropic says Opus 5.5 is available to Claude Pro, Max, Team and Enterprise users. Developers can access it through the Claude Platform, and Anthropic also lists availability through Amazon Web Services, Google Cloud and Microsoft Foundry.
Fast mode is available in Claude Code and on the Claude Platform for workloads where latency is worth the higher per-token price.
Should developers migrate from Opus 5?
If an application already uses Opus 5, Opus 5.5 is worth testing because Anthropic is explicitly targeting better performance and lower typical workload cost. Migration should still be evaluated rather than assumed.
A practical migration test should compare:
- task success rate on real prompts and agent traces;
- total input, output and cache-read tokens;
- latency and time to complete multi-step jobs;
- human correction or review time;
- tool-use reliability and failure recovery;
- total cost per successfully completed task.
FAQ
When was Claude Opus 5.5 released?
Anthropic announced Claude Opus 5.5 on September 22, 2026.
What is the Claude Opus 5.5 API model name?
The model identifier published by Anthropic is claude-opus-5-5.
How much does Claude Opus 5.5 cost?
Standard Claude Platform pricing is $4 per million input tokens and $20 per million output tokens. Cache reads are $0.20 per million tokens. Anthropic also offers a faster mode at higher pricing.
Is Claude Opus 5.5 good for coding?
Anthropic positions it as its strongest Opus model for agentic coding, including long-running work in large codebases, debugging, refactoring and code review.
Is Claude Opus 5.5 cheaper than Opus 5?
Yes on published token pricing. Anthropic says Opus 5.5 input and output token prices are 20% below Opus 5, cache reads are 60% cheaper, and typical token-billed workloads cost about 40% less overall.
Bottom line
Claude Opus 5.5 is less about a new name and more about making Anthropic’s premium Opus tier more practical for continuous, agentic work. Lower pricing, cheaper cache reads and improvements aimed at long-running coding and professional workflows make it an important model to evaluate for teams using AI as an active worker rather than a simple assistant.
The right choice still depends on the workload. Developers should compare Opus 5.5 with alternatives such as GPT-6 Sol using real tasks, real tools and total cost per successful outcome.
