No free plan. The cheapest way in is GPT-5.4 (Flagship) at $2.50 input / $15.00 output per 1M tokens. Consider free alternatives in the ai models category if budget is tight.
OpenAI Responses API focuses on professional ai models features that require ongoing development and support, justifying paid-only tiers.
Look for free trials or entry-level plans. Some tools offer money-back guarantees for risk-free testing.
Yes, see the alternatives section below for free ai models tools with similar features.
Consider the feature comparison and your specific needs. Professional ai models tools often justify their cost through time savings and advanced capabilities.
See OpenAI Responses API plans and find the right tier for your needs.
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Last verified March 2026