Code Arena WebDev: DeepSeek V4.1 Flash tops open models at ~10x lower cost than Kimi K3

CloudDog @CloudDogxOriginally posted 2026.10.19

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DeepSeek-V4.1-Flash-20261017 (Max) just hit #1 among open models on Code Arena: WebDev, passing Kimi K3 (Max) at about 10x lower cost, per the latest @arena rankings. This keeps happening: a flash-class model climbs a coding leaderboard while costing an order of magnitude less. For agentic coding loops — hundreds of tool calls per task — the per-call price gap compounds fast, so every notch a cheap model climbs quietly rewrites the default stack. Open models aren't just closing the quality gap. They're undercutting on price at the same time.