Mistral Medium 3.5 vs o3

Mistral Medium 3.5 costs 25% less on input and 6% less on output than o3 ($1.50 / $7.50 versus $2.00 / $8.00 per million tokens). Mistral Medium 3.5 accepts more context (262 K). On capabilities, o3 has a reasoning mode. Mistral Medium 3.5 and o3 offer a batch tier at half price for jobs that do not need an immediate answer.

Mistral Medium 3.5 is cheaper: $1.50 per million input tokens and $7.50 per million output tokens, versus $2.00 / $8.00 for o3.

Mistral Medium 3.5 accepts 262 K tokens of context; o3 accepts 200 K.

Mistral Medium 3.5 was released on 05/01/2026; o3 on 04/16/2025.

With 1,500 input and 400 output tokens per request: Mistral Medium 3.5: $52.50; o3: $62.00 a month, at list price.

From the public catalogs of OpenRouter, models.dev and LiteLLM, which publish each provider's list prices. They sync once a day and the last update date is shown above the comparison.

It is what the provider charges per million tokens you send (input) or the model generates (output). A token is roughly 4 characters. Output almost always costs more than input.