The cheapest OpenAI model is gpt-oss-20b at $0.029 per million input tokens. gpt-oss-120b ($0.039) and GPT-5 Nano ($0.050) round out the top three.
AI models ranked by input token price. The most affordable large language model APIs, from budget open-weight models to discounted frontier models.
The cheapest OpenAI model is gpt-oss-20b at $0.029 per million input tokens. gpt-oss-120b ($0.039) and GPT-5 Nano ($0.050) round out the top three.
gpt-oss-120b ($0.039) is the closest alternative on this metric, followed by GPT-5 Nano ($0.050). See the full ranking above for the tradeoffs.
modelgrep tracks 62 OpenAI models with live benchmarks, speed, latency and per-provider pricing, led on intelligence by GPT-5.4. 25 of them qualify for this ranking.