Claude Opus 4.5vsGemini 2.5 Flash Preview
Claude Opus 4.5 is the newer model, released after Gemini 2.5 Flash Preview.
| Spec | Claude Opus 4.5 | Gemini 2.5 Flash Preview |
|---|---|---|
| Input price | — | $0.15/M tokens |
| Output price | — | $0.6/M tokens |
| Context window | — | 1.0M tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Nov 2025 | Apr 2025 |
| SWE-bench Verified | 80.9% | 60.4% |
Our Verdict
Claude Opus 4.5
Gemini 2.5 Flash PreviewRunner-up
Not enough votes to call it. On the specs, Claude Opus 4.5 has the edge: bigger model tier, newer.
Too close to call
API pricing
Cost per 1M tokens
Claude Opus 4.5
Input
—
Output
—
Gemini 2.5 Flash Preview
Input
$0.15
Output
$0.60
Where to run it
4 hosts
Gemini 2.5 Flash Preview
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 9 Sep 2026.
Writing DNA
Style Comparison
Similarity
35%
Claude Opus 4.5 uses 18.5x more emoji
Claude Opus 4.5
Gemini 2.5 Flash Preview
66%Vocabulary51%
51wSentence Length15w
0.82Hedging0.70
6.0Bold4.1
4.5Lists3.3
0.18Emoji0.00
1.46Headings0.09
0.05Transitions0.24
Based on 27 + 12 text responses
Research
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FAQ
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