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Claude Sonnet 5.5 vs Muse Spark 1.3

Claude Sonnet 5.5Anthropic
Muse Spark 1.3Meta
Our take

Claude Sonnet 5.5 wins 3 of 4 categories, but Muse Spark 1.3 is 2.0× cheaper for everyday text work. Pick Claude Sonnet 5.5 when quality matters most, Muse Spark 1.3 at volume.

Overall79Best68
Coding87Best75
Writing74Best70
Support6971Best
Value69Best62
Input / 1M$2.00$1.25Best
Output / 1M$10.00$4.25Best
Blended / 1M$4.00$2.00Best
Context window1M1MBest
Open weightsNoNo
Released28 Sept 20262 Sept 2026

Your monthly bill

50k
Claude Sonnet 5.5$800
Muse Spark 1.3$400Cheapest
List prices, a quarter of the tokens as output. Scores are provisional, from Arena and Epoch AI.