Claude Opus 4.5 vs Solar Pro 3

Compare Claude Opus 4.5 by Anthropic against Solar Pro 3 by Upstage, tested across 39 shared challenges. Updated April 2026.

Which is better, Claude Opus 4.5 or Solar Pro 3?

Claude Opus 4.5 and Solar Pro 3 are both competitive models. Compare their real outputs side by side below.

Key Differences Between Claude Opus 4.5 and Solar Pro 3

Claude Opus 4.5 is made by anthropic while Solar Pro 3 is from upstage.

Our Verdict
Claude Opus 4.5
Claude Opus 4.5
Solar Pro 3
Solar Pro 3Runner-up

No community votes yet. On paper, Claude Opus 4.5 has the edge — bigger model tier, major provider backing.

Too close to call
Writing DNA

Style Comparison

Similarity
99%

Claude Opus 4.5 uses 2.9x more headings

Claude Opus 4.5
Solar Pro 3
64%Vocabulary50%
55wSentence Length21w
0.86Hedging0.42
5.8Bold6.5
4.5Lists2.2
0.15Emoji0.17
1.59Headings0.56
0.05Transitions0.12
Based on 24 + 18 text responses
vs

Ask them anything yourself

Claude Opus 4.5Solar Pro 3

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026
Free preview13 of 58 slides
FAQ

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