Models · Claude
Claude Opus 5
Asked for a few hundred random integers, Claude Opus 5 does not pick evenly. This page is the shape of that preference, built from 36 recorded answers containing 10609 numbers, and it is what the identify tool compares a pasted reply against.
- Bank id
claude-opus-5- Family
- Claude
- Collected through
- API
- Collected on
- Not recorded upstream
- Status
- Inherited from ModelTrace; serving identity not independently verified
- Distinct values used
- 354 of 355
- Prompt environments
- 12 of 12
Capability and price
- Sold by
- Anthropic
- Intelligence index
- 51 · v4.3.2, scored as max
- Index rank
- Not ranked — the index marks this configuration superseded by Claude Opus 5.5.
- Input, per 1M tokens
- 5.00
- Output, per 1M tokens
- 25.00
- Blended, per 1M tokens
- 10.00
- Price rank
- Not ranked
- Context window
- 1,000,000 tokens
Read on 2026-10-02, not measured here: index page · price page
Distribution
Selected number 205
| Model | Times chosen | Share |
|---|---|---|
| Claude Opus 5 | 63 | 0.59% |
Favourite numbers
| Number | Times chosen | Share |
|---|---|---|
| 205 | 63 | 0.59% |
| 96 | 61 | 0.57% |
| 271 | 60 | 0.57% |
| 129 | 58 | 0.55% |
| 143 | 58 | 0.55% |
| 240 | 55 | 0.52% |
| 66 | 54 | 0.51% |
| 68 | 54 | 0.51% |
| 88 | 53 | 0.50% |
| 87 | 52 | 0.49% |
| 152 | 52 | 0.49% |
| 92 | 51 | 0.48% |
How reliably it is recognised
In held-out testing across all twelve prompt environments, 11 of 12 three-answer runs named this model with a clear margin, 1 were close calls inside its family, 0 had only a weak match, and 0 named a different model with a clear margin.
With this model removed from the bank and its own answers scored against the rest, 5 of 12 runs still named another model with a clear margin, 4 were close calls inside the family, and 3 had only a weak match. Its answers landed most often on Claude Opus 4.8 (12 of 12). That is the number to keep in mind if you are testing a version that is not listed here.
Both measurements count the status the site attaches to the first-ranked model, not the bare ranking alone. The methodology page explains how they were made and what they leave out.