GPT-5.4 vs GPT-5.4 Mini, task by task: where the 3.3x price gap is worth paying and where it isn't

OpenAI ships GPT-5.4 Mini at $0.75 per million input tokens and $4.50 per million output tokens. GPT-5.4 ships at $2.50 and $15 — a 3.3x price multiplier across both input and output. (Note: the older GPT-4o family had a 16x gap between mini and standard; the GPT-5 generation narrowed it. The wedge is smaller in absolute ratio but still meaningful at production volume.) The implication: on workloads where mini produces equivalent quality, paying 3.3x for GPT-5.4 is structural waste. The honest e...