Is DeepSeek: DeepSeek V4 Flash 0731 or OpenAI: GPT-5.4 cheaper?
DeepSeek: DeepSeek V4 Flash 0731 is cheaper ($0.45 / 1M tokens input / $1.33 / 1M tokens output) vs OpenAI: GPT-5.4 ($2.50 / 1M tokens input / $15 / 1M tokens output). Actual cost depends on your input/output token mix — estimate it with the pricing calculator.