Claude Sonnet 4.5 vs Muse Spark Open
Wins 0 of 7 areas
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Wins 7 of 7 areas
Coding · Agents · Reasoning · Facts · Images and charts · Math · Long documents
Muse Spark Open is the stronger all-rounder.
Scores updated · 16 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 thinking03Muse Spark Open3 of 3 tests
- FactsGetting facts right instead of making them up03Muse Spark Open3 of 3 tests
- CodingWriting and fixing software02Muse Spark Open2 of 2 tests
- AgentsCarrying out multi-step tasks on its own02Muse Spark Open2 of 2 tests
- MathCompetition and research-level math02Muse Spark Open2 of 2 tests
- Images and chartsUnderstanding pictures, charts and video01Muse Spark Open1 of 1 test
- Long documentsFinding answers in very long texts01Muse Spark Open1 of 1 test
Images and charts 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.
Muse Spark Open costs 69% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Muse Spark Open pulls ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+45.9points ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+29.3points ahead
- Very hard expert questions across many subjectsHumanity's Last Exam+26.1points ahead
Where Claude Sonnet 4.5 pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 16 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingMuse Spark Open
- Terminal-Bench 2.1Muse Spark Open by 20.655.876.4+20.6
- SciCodeMuse Spark Open by 12.745.758.4+12.7
AgentsMuse Spark Open
- GDPValMuse Spark Open by 24.620.545.1+24.6
- Terminal-Bench 4.0Muse Spark Open by 8.108.1+8.1
ReasoningMuse Spark Open
- Humanity's Last ExamMuse Spark Open by 26.117.843.9+26.1
- CritPtMuse Spark Open by 13.81.114.9+13.8
- GPQA DiamondMuse Spark Open by 5.683.489+5.6
FactsMuse Spark Open
- SimpleQA VerifiedMuse Spark Open by 25.930.756.6+25.9
- AA-Omniscience · Non-hallucinationMuse Spark Open by 2550.975.9+25
- AA-Omniscience · AccuracyMuse Spark Open by 6.432.939.3+6.4
Images and chartsMuse Spark Open
- MMMU-ProMuse Spark Open by 12.268.780.9+12.2
MathMuse Spark Open
- FrontierMath Tiers 1-3 (v2)Muse Spark Open by 45.923.969.8+45.9
- FrontierMath Tier 4Muse Spark Open by 29.32.431.7+29.3
Other results2 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-OmniscienceMuse Spark Open by 24.8-0.124.6+24.8
- AA IntelligenceMuse Spark Open by 18.220.738.9+18.2
Questions people ask
Which is better, Claude Sonnet 4.5 or Muse Spark Open?
Muse Spark Open wins all seven areas where both have results: coding, agents, reasoning, facts, images and charts, math and long documents. Claude Sonnet 4.5 wins none.
Which is better for coding?
Muse Spark Open. It wins 2 of the 2 coding tests both models report; Claude Sonnet 4.5 wins none.
Which is cheaper?
Claude Sonnet 4.5 costs $3.00 per million input tokens and $15.00 per million output tokens; Muse Spark Open costs $1.25 and $4.25. That makes Muse Spark Open about 69% cheaper for the same work.
How do you compare the two?
We use the 16 benchmark tests both models have published scores on. The verdict counts the 14 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 2 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.