Claude Opus 5.5 benchmarks, pricing and specs
Claude Opus 5.5 is an Anthropic model released on September 22, 2026 that takes text and image input and produces text. It costs $4 per 1M input tokens and $20 per 1M output tokens and accepts up to 1,000,000 tokens of context. It scores 1507 Elo on Arena Text, #1 of 39 current models (Arena, measured October 8, 2026).
- Per 1M input tokens
- $4
- Per 1M output tokens
- $20
- Context window
- 1M
- Arena Text
- 1507 Elo · #1/39
Data verified October 12, 2026 · Dataset 2026-10-12
Key facts
- Provider
- Anthropic
- Model family
- Claude Opus
- Release date
- September 22, 2026
- Status
- Current
- Access
- API only
- API model id
- Not reported
- Context window
- 1,000,000 tokens
- Max output
- 128,000 tokens
- Input
- text, image
- Output
- text
- Task families
- text, multimodal
- Declared capabilities
- reasoning
Claude Opus 5.5 pricing
It is the #8 most expensive of 37 current text models priced per 1M input tokens.
Independent benchmark results
Scores come from independent evaluators that ran the model themselves, pinned to a dated snapshot. Rank is among current models in the same snapshot. Anthropic's own launch figures are listed under strengths with the publisher named, because they are not measured the same way.
| Benchmark | Score | Rank | Measured | Source |
|---|---|---|---|---|
| Arena Text | 1507 Elo | #1 of 39 | October 8, 2026 | Arena · 2026-10-12 |
| GPQA Diamond | 90.6% | #22 of 37 | October 12, 2026 | Epoch AI · 2026-10-12 |
| FrontierMath Tiers 1-3 (v2) | 91.2% | #3 of 37 | October 12, 2026 | Epoch AI · 2026-10-12 |
| SimpleQA Verified | 72.2% | #4 of 34 | October 12, 2026 | Epoch AI · 2026-10-12 |
Strengths, cautions and best uses
Strengths
- Anthropic's recommended default for most workloads, taking that role from Claude Opus 5, at $4 per million input and $20 per million output
- 1M-token context window with a 128,000-token maximum output, and adaptive thinking that is always on
- Cache reads are 0.05x base input ($0.20 per million) rather than the usual 0.1x, which matters most in agent loops that replay a large prefix
Cautions
- The API effort default is medium here, not high as on Claude Fable 5.1 and Claude Sonnet 5.5, so a like-for-like comparison has to set effort explicitly
- The 4.7-generation tokenizer produces roughly 30% more tokens for the same text than Claude Sonnet 4.6 and earlier, so per-token rates do not compare directly across generations
Best for
- Long-running agentic coding and knowledge work as the general-purpose default
- Cache-heavy agent loops where the 0.05x read multiplier compounds
Alternatives to Claude Opus 5.5
The closest current textmodels by price. The cheapest model that scores as well or better is listed first; failing that, the cheapest one within 3% of the benchmark's scale.
Cheaper, similar score
Gemini 3.8 Flash
- 81% cheaper per 1M input tokens, $0.75 vs $4
- 10 points lower on Arena Text, 1497 vs 1507
- From Google
GPT-5.6 Sol
- Same price per 1M input tokens, $4
- 22 points lower on Arena Text, 1485 vs 1507
- From OpenAI
GPT-5.5
- 25% more per 1M input tokens, $5 vs $4
- 25 points lower on Arena Text, 1482 vs 1507
- From OpenAI
Kimi K3
- 25% cheaper per 1M input tokens, $3 vs $4
- 19 points lower on Arena Text, 1488 vs 1507
- From Moonshot Kimi
Compare Claude Opus 5.5 with
Articles about Claude Opus 5.5
- GPT-6 Sol vs Claude Opus 5.5, Plus Luna: Best Value per TaskSeptember 24, 2026
- Claude Opus 5.5 Benchmarks: What the Chart Shows and HidesSeptember 23, 2026
- Claude Opus 5.5: Tops the Independent Index at a Lower PriceSeptember 23, 2026
Other Claude Opus models
Claude Opus 5.5 FAQ
How much does Claude Opus 5.5 cost?
Claude Opus 5.5 costs $4 per 1M input tokens and $20 per 1M output tokens at the standard tier. It is the #8 most expensive of 37 current text models priced per 1M input tokens. Source: Anthropic, verified October 11, 2026.
What is the context window of Claude Opus 5.5?
Claude Opus 5.5 accepts up to 1,000,000 tokens of context. It can return up to 128,000 tokens in one response. That ranks #24 of 44 current text models by context length.
How does Claude Opus 5.5 score on independent benchmarks?
Claude Opus 5.5 scores 1507 Elo on Arena Text, #1 of 39 current models (Arena, measured October 8, 2026), 90.6% on GPQA Diamond, #22 of 37 current models (Epoch AI, measured October 12, 2026) and 91.2% on FrontierMath Tiers 1-3 (v2), #3 of 37 current models (Epoch AI, measured October 12, 2026). These are independent evaluations, not Anthropic's own launch figures.
Is Claude Opus 5.5 open source or API only?
Claude Opus 5.5 is available through Anthropic's API only; its weights are not published.
What are the best alternatives to Claude Opus 5.5?
The closest current alternatives by price and measured performance are Gemini 3.8 Flash (81% cheaper per 1M input tokens, $0.75 vs $4), GPT-5.6 Sol (same price per 1M input tokens, $4), GPT-5.5 (25% more per 1M input tokens, $5 vs $4) and Kimi K3 (25% cheaper per 1M input tokens, $3 vs $4).
Sources
- Claude models overview · Anthropic · official · verified October 11, 2026
- Claude API pricing · Anthropic · official · verified October 11, 2026
- Epoch AI Benchmarking Hub data (benchmark_data.zip) · Epoch AI · independent · verified October 12, 2026 · CC-BY-4.0
- Arena leaderboard dataset (lmarena-ai/leaderboard-dataset) · Arena · independent · verified October 12, 2026 · CC-BY-4.0
Cite this page
Van Data Team. "Claude Opus 5.5 Benchmarks, Pricing and Specs." AI Model Benchmark Dataset 2026-10-12. https://vandatateam.com/ai-model-benchmarks/claude-opus-5-5
Reuse the data: JSON · CSV · or explore every model in the AI model benchmark comparison.
Production evaluation
Deciding whether Claude Opus 5.5 fits your workload?
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