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Kimi K3.1 Pro vs Muse Spark 1.3

Kimi K3.1 ProMoonshot AI
Muse Spark 1.3Meta
Our take

Kimi K3.1 Pro wins 1 of 1 categories, but Muse Spark 1.3 is 2.0× cheaper for everyday text work. Pick Kimi K3.1 Pro when quality matters most, Muse Spark 1.3 at volume.

Overall–68
Coding79Best75
Writing–70
Support–71
Value–62
Input / 1M$2.00$1.25Best
Output / 1M$10.00$4.25Best
Blended / 1M$4.00$2.00Best
Context window1M1M
Open weightsNoNo
Released23 Oct 20262 Sept 2026

Your monthly bill

50k
Kimi K3.1 Pro$800
Muse Spark 1.3$400Cheapest
List prices, a quarter of the tokens as output. Scores are provisional, from Arena and Epoch AI.