opus-5.5
Public AI IQ model profile with source-backed benchmark results and derived ranking context.
opus-5.5 API pricing — full price table, workload cost examples, and cheaper alternatives.
Release and Capabilities
| Public release | 2026-09-22 |
|---|---|
| Modalities | text, image |
| Context window | 1,000,000 tokens |
Available through the Claude API as claude-opus-5-5 and Claude applications.
Publisher-reported capabilities
- Adaptive reasoning for long-running coding and knowledge work.
- Supports a 1M-token context window and 128K output tokens.
- Standard token prices are 20% lower than Opus 5.
Limitations and availability caveats
- Biology and cybersecurity safeguards restrict some requests.
- Artificial Analysis evaluates the default refusal-fallback configuration; those results are not isolated no-fallback measurements.
Official release and model references
Measured Coverage and Estimates
Opus 5.5 has 27 of 39 tracked IQ benchmark inputs across 7 of 7 dimensions. Raw benchmark tables contain source-backed results only. Derived IQ combines all six dimensions using the shared scoring methodology, including estimates where direct coverage is incomplete. Configured predecessor references: Opus 5. A reference is an estimation input, not evidence that this model has the predecessor's measured results.
Among dimensions with direct benchmark coverage, this profile's highest estimated scores are Programmatic Reasoning (IQ 155) and Mathematical Reasoning (IQ 149). These dimension estimates can include statistical adjustments or predecessor priors; they are not raw benchmark percentages or claims of real-world task success.
Benchmark versions, evaluation harnesses, and coverage affect comparisons; a missing result is not a score of zero. See the scoring methodology for estimation and uncertainty limits.
IQ Dimensions
| Dimension | IQ | Coverage |
|---|---|---|
| Abstract Reasoning | 132 | 3/5 |
| Mathematical Reasoning | 149 | 4/5 |
| Academic Reasoning | 139 | 4/6 |
| Programmatic Reasoning | 155 | 4/6 |
| Computer Use | 147 | 2/5 |
| Reliability | 134 | 5/6 |
| Knowledge Work | 135 | 5/6 |
Benchmark Results
Compare
Frequently Asked Questions
- What is the IQ of opus-5.5?
- opus-5.5 has an estimated IQ of 142, which ranks #2 out of 164 public models on the AI IQ leaderboard. The score combines seven equally weighted reasoning dimensions using measured benchmark results and conservative estimates for missing coverage.
- How much does opus-5.5 cost?
- opus-5.5 costs $4.00 per million input tokens and $20.00 per million output tokens. Adjusted for how many tokens it actually consumes on real tasks, its effective cost works out to $35.08 per million input-plus-output tokens.
- Is opus-5.5 open source?
- No — opus-5.5 is a proprietary model. Its weights are not publicly available, so it is used through hosted APIs and products.
- When was opus-5.5 released?
- opus-5.5 was publicly released on September 22, 2026.
- How large is the context window of opus-5.5?
- opus-5.5 supports a context window of 1,000,000 tokens — the amount of text it can consider in a single request.
- How fast is opus-5.5?
- In independent measurements, opus-5.5 generates about 95 tokens per second, with a typical response time of about 697 seconds.