Claude Opus 4.5 vs Qwen3 4B
Wins 4 of 5 areas
Coding · Reasoning · Long documents · Following instructions
Wins 1 of 5 areas
Facts
Claude Opus 4.5 is the stronger all-rounder.Qwen3 4B is better at facts.
Scores updated · 13 tests both models report · How we compare
Where each one wins
Tests won in each of the five areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software20Claude Opus 4.52 of 2 tests
- ReasoningHard problems that need careful thinking20Claude Opus 4.52 of 2 tests
- Long documentsFinding answers in very long texts10Claude Opus 4.51 of 1 test
- Following instructionsDoing exactly what it is asked10Claude Opus 4.51 of 1 test
- FactsGetting facts right instead of making them up01Qwen3 4B1 of 1 test
Facts, long documents and following instructions rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Claude Opus 4.5 pulls ahead
- Recent programming contest problemsLiveCodeBench v6+48.7points ahead
- Code for real scientific research problemsSciCode+46points ahead
- Graduate-level biology, physics and chemistry questionsGPQA Diamond+34.4points ahead
Where Qwen3 4B pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 13 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Opus 4.5
- LiveCodeBench v6Claude Opus 4.5 by 48.784.836.1+48.7
- SciCodeClaude Opus 4.5 by 4649.53.5+46
ReasoningClaude Opus 4.5
- GPQA DiamondClaude Opus 4.5 by 34.486.652.2+34.4
- Humanity's Last ExamClaude Opus 4.5 by 25.730.14.4+25.7
FactsQwen3 4B
- Vectara HHEM hallucination ratelower is betterQwen3 4B by 5.210.95.7+5.2
Following instructionsClaude Opus 4.5
- IFBenchClaude Opus 4.5 by 25.55832.5+25.5
Other results6 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- τ²-Bench Telecom (AA run)Claude Opus 4.5 by 70.589.519+70.5
- AA IntelligenceClaude Opus 4.5 by 21.929.17.2+21.9
- MMLU-ProClaude Opus 4.5 by 19.589.570+19.5
- vectara_factual_consistencyQwen3 4B by 5.289.194.3+5.2
- vectara_answer_rateQwen3 4B by 1.298.799.9+1.2
- vectara_avg_summary_lengthtie114.5104.7tie
Questions people ask
Which is better, Claude Opus 4.5 or Qwen3 4B?
Claude Opus 4.5 wins four of the five areas where both have results: coding, reasoning, long documents and following instructions. Qwen3 4B wins facts.
Which is better for coding?
Claude Opus 4.5. It wins 2 of the 2 coding tests both models report; Qwen3 4B wins none.
How do you compare the two?
We use the 13 benchmark tests both models have published scores on. The verdict counts the 7 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 6 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.