Claude Opus 4.5 vs Muse Spark
Wins 1 of 7 areas
Agents
Wins 4 of 7 areas
Reasoning · Facts · Images and charts · Following instructions
Muse Spark wins more areas, narrowly.Claude Opus 4.5 is better at agents.
Scores updated · 29 tests both models report · How we compare
Where each one wins
Tests won in each of the seven 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.
- ReasoningHard problems that need careful thinking04Muse Spark4 of 4 tests
- Images and chartsUnderstanding pictures, charts and video02Muse Spark2 of 2 tests
- Following instructionsDoing exactly what it is asked02Muse Spark2 of 2 tests
- FactsGetting facts right instead of making them up12Muse Spark2 of 3 tests
- AgentsCarrying out multi-step tasks on its own10Claude Opus 4.51 of 1 test
- CodingWriting and fixing software22Even2 each · 1 tie
- Long documentsFinding answers in very long texts00Even0 each · 1 tie
Agents and long documents 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 three tests each model wins by the widest margin. Scores are out of 100.
Where Muse Spark pulls ahead
- Short factual questions, answered correctlySimpleQA Verified+20.6points ahead
- Reasoning about charts from research papersCharXiv (RQ)+19.2points ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+17.9points ahead
Where Claude Opus 4.5 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+23.2points ahead
- Real work tasks from 44 professionsGDPVal+22.2points ahead
- Fixes real GitHub issues in Python projectsSWE-bench Verified+3.5points ahead
Every test, side by side
All 29 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingEven
- LMArena · WebDevMuse Spark by 71 rating points14691540+71 rating
- SWE-bench VerifiedClaude Opus 4.5 by 3.580.977.4+3.5
- SciCodeMuse Spark by 249.551.5+2
- Terminal-Bench HardClaude Opus 4.5 by 1.54745.5+1.5
- SWE-bench Protie5252.4tie
ReasoningMuse Spark
- Humanity's Last ExamMuse Spark by 10.630.140.7+10.6
- CritPtMuse Spark by 6.74.611.3+6.7
- ARC-AGI-2Muse Spark by 4.937.642.5+4.9
- GPQA DiamondMuse Spark by 1.886.688.4+1.8
FactsMuse Spark
- AA-Omniscience · Non-hallucinationClaude Opus 4.5 by 23.23915.8+23.2
- SimpleQA VerifiedMuse Spark by 20.645.766.3+20.6
- AA-Omniscience · AccuracyMuse Spark by 346.649.6+3
Images and chartsMuse Spark
- CharXiv (RQ)Muse Spark by 19.267.286.4+19.2
- MMMU-ProMuse Spark by 6.57480.5+6.5
Following instructionsMuse Spark
- IFBenchMuse Spark by 17.95875.9+17.9
- Multi-ChallengeMuse Spark by 16.55975.5+16.5
Other results11 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.
- AA Agentic IndexClaude Opus 4.5 by 30.959.628.7+30.9
- ZeroBenchMuse Spark by 30333+30
- Artificial Analysis Coding IndexMuse Spark by 10.847.858.6+10.8
- frontiermath_tier_4_v1Muse Spark by 10.44.214.6+10.4
- CyberGymClaude Opus 4.5 by 7.150.643.5+7.1
- AA-OmniscienceClaude Opus 4.5 by 6.8147.2+6.8
- AA IntelligenceMuse Spark by 2.229.131.3+2.2
- τ²-Bench Telecom (AA run)Muse Spark by 289.591.5+2
- SimpleVQAMuse Spark by 1.669.771.3+1.6
- DeepSearchQA (F1)Claude Opus 4.5 by 1.376.174.8+1.3
- Terminal-Bench 2.0tie59.359tie
Questions people ask
Which is better, Claude Opus 4.5 or Muse Spark?
Muse Spark wins four of the seven areas where both have results: reasoning, facts, images and charts and following instructions. Claude Opus 4.5 wins agents. They are level on coding and long documents.
Which is better for coding?
Neither. They win 2 coding tests each of the 5 both models report, and 1 is a tie.
How do you compare the two?
We use the 29 benchmark tests both models have published scores on. The verdict counts the 18 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 11 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.