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Claude Opus 5.5 vs DeepSeek V4.1 Flash 1017

Claude Opus 5.5Anthropic
DeepSeek V4.1 Flash 1017DeepSeek
Our take

Claude Opus 5.5 wins 1 of 1 categories, but DeepSeek V4.1 Flash 1017 is 15.2× cheaper for everyday text work. Pick Claude Opus 5.5 when quality matters most, DeepSeek V4.1 Flash 1017 at volume.

Overall97–
Coding100Best74
Writing100–
Support90–
Value83–
Input / 1M$4.00$0.30Best
Output / 1M$20.00$1.20Best
Blended / 1M$8.00$0.53Best
Context window1M1MBest
Open weightsNoYes
Released22 Sept 202617 Oct 2026

Your monthly bill

50k
Claude Opus 5.5$1.6k
DeepSeek V4.1 Flash 1017$105Cheapest
List prices, a quarter of the tokens as output. Scores are provisional, from Arena and Epoch AI.