Head to head
Claude Opus 5 vs Claude Sonnet 5
Which is better, Claude Opus 5 or Claude Sonnet 5?
Claude Opus 5 finishes ahead of Claude Sonnet 5 on the index, 88.5 to 87.9. It is the stronger of the two on Craft, while Claude Sonnet 5 still leads on Speed and Value. Both are scored on the same rubric, in the same week, and neither placing is sponsored.
Updated
Claude Opus 5
03 of 53
88.5
Most of the flagship, at half the price. The one to reach for by default.
Claude Sonnet 5
04 of 53
87.9
The coding workhorse: near the top on real software tasks, at a working price.
The four scores, side by side
| Score | Claude Opus 5 | Claude Sonnet 5 | Difference |
|---|---|---|---|
| Craft | 93 | 89 | +4 |
| Speed | 82 | 88 | +6 |
| Control | 90 | 89 | +1 |
| Value | 78 | 84 | +6 |
| Index score | 88.5 | 87.9 | +0.6 |
Which to pick
Pick Claude Opus 5 unless Speed and Value is what decides it for you, which is exactly where Claude Sonnet 5 is the better answer.
Claude Opus 5
Opus 5 is the model that makes the rest of Anthropic's line-up hard to justify. It gives up a little at the very top of the reasoning range and takes half off the bill, while staying quick enough to sit inside an editor or an agent loop. If you are choosing one paid frontier model and do not want to think about it again this quarter, this is the honest answer.
Where it shines
- Frontier-class output without the flagship's price
- Fast enough for interactive use, unlike the tier above it
- Excellent at long-context reading of an existing codebase
Claude Sonnet 5
Sonnet 5 is what most coding agents actually run on, and the benchmark gap to the tier above it is smaller than the price gap. It applies patches that compile, follows a repository's existing conventions, and holds up over the long tool-calling chains that agent frameworks generate. Anthropic has been discounting it, so check the current rate before you build a budget on it.
Where it shines
- Among the strongest models on verified software engineering tasks
- Priced to run continuously rather than occasionally
- Reliable tool calling over long chains, which is what breaks weaker models