Claude Opus 4.5 vs Claude Sonnet 4.5: what 6 developers chose.
419 opinions. 6 developers named a direct preference: Claude Opus 4.5 6–0. Approval is 78% vs 57%.
If you want code quality, choose Claude Opus 4.5. If you want autonomy, choose Claude Sonnet 4.5. The 6–0 direct split is not a landslide; it is a difference in working style.
Choose Claude Opus 4.5 if you…
- Need long autonomous runs on complex work
- Work in large codebases and want stronger quality signals
- Can absorb a higher cost for stronger output
Choose Claude Sonnet 4.5 if you…
- Want a cheaper option for routine coding
- Keep a human in the loop on familiar patterns
- Need spec-driven work with tight review
Code quality for Claude Opus 4.5. Autonomy for Claude Sonnet 4.5.
Net sentiment per topic: praise minus complaints, as a share of mentions. Positive means more praise than complaints. Hover a dot for the raw counts.
Net sentiment = praise minus complaints, as a share of each tool's mentions. The dot lanes are only for readability; position is the score.
View data table
| Topic | Claude Opus 4.5 | Claude Sonnet 4.5 | Mentions |
|---|---|---|---|
| Code quality | +62 | +2 | 148 / 43 |
| Autonomy | +76 | +25 | 34 / 8 |
| Reliability | +3 | -33 | 35 / 15 |
| Cost & pricing | +67 | 0 | 12 / 4 |
The same decision, from both sides.
Paraphrased from comments where a developer named a preference or described a switch. Each links to the original.
Picked Claude Opus 4.5 6 developers
Used Sonnet 4.5 heavily on a complex project for a 10-15% productivity gain but found Opus 4.5 more autonomous with less supervision.
Saw a large jump from Sonnet 4.5 to Opus 4.5 and treated Opus as the decisive upgrade while also trying Codex GPT 5.3.
The team switched its default coding agent from Sonnet 4.5 to Opus 4.5, accepted about triple the cost, and found the quality worth it.
Thanks for posting this. It's a nice reminder that despite all the noise from hype-mongers and skeptics in the past few years, most of us here are just trying to figure this all out with an open mind and are ready to change our opinions when the facts change. And a lot of people in the industry that I respect on HN or elsewhere have changed their minds about this stuff in the last year, having previously been quite justifiably skeptical. We're not in 2023 anymore. If you were someone saying at the start of 2025 "this is a flash in the pan and a bunch of hype, it's not going to fundamentally ch
Picked Claude Sonnet 4.5 0 developers
No explicit switches recorded.
The numbers.
| Metric | Claude Opus 4.5 | Claude Sonnet 4.5 |
|---|---|---|
| Approval | 78% | 57% |
| Last 90 days | 90% | – |
| Opinions | 322 | 97 |
| Developers | 259 | 91 |
| First-hand opinions | 254 | 93 |
| Direct picks | 6 | 0 |
| Type | Model | Model |
| Made by | — | — |
Related matchups.
Claude Opus 4.5 vs Claude Opus 4.6
7–4 direct picks, and a clear difference in what developers optimise for.
Claude Opus 4.5 vs GPT-5.2
7–3 direct picks, and a clear difference in what developers optimise for.
Claude Opus 4.5 vs Gemini 3
5–1 direct picks, and a clear difference in what developers optimise for.
How to read this comparison.
Approval is the positive share of opinions that took a side, with the rank based on the lower bound of a 90% confidence interval. Direct picks count comments where a developer explicitly preferred one tool or described switching. Small samples are noisier; check the opinion counts.
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