OPENAI VS MISTRAL
GPT-5.5 Pro vs Mistral Medium 3.5
Mistral Medium 3.5 is about 23x cheaper than GPT-5.5 Pro on a blended 3:1 input:output rate — the same 10K-in/2K-out request costs $0.03 vs $0.66. GPT-5.5 Pro has the larger context window (1,047,576 vs 262,144 tokens).
Pricing verified
API pricing per 1M tokens
| Model | Input / 1M tokens | Output / 1M tokens | Blended (3:1 mix) |
|---|---|---|---|
| GPT-5.5 Pro | $30.00 | $180.00 | $67.50 |
| Mistral Medium 3.5 | $1.50 | $7.50 | $3.00 |
Rates from official OpenAI pricing and official Mistral pricing, checked 2026-08-11.
What a real workload costs
Example: one request with 10,000 input tokens and 2,000 output tokens, then that request at 100,000 runs per month.
| Model | Per request (10K in / 2K out) | Per month (100K requests) | Monthly delta |
|---|---|---|---|
| GPT-5.5 Pro | $0.66 | $66,000 | +$63,000 |
| Mistral Medium 3.5 | $0.03 | $3,000 | — |
Model your own prompt sizes and volumes in the token cost analyzer, or check caching savings with the prompt caching calculator.
Specs side by side
| Spec | GPT-5.5 Pro | Mistral Medium 3.5 |
|---|---|---|
| Provider | OpenAI | Mistral |
| Context window | 1,047,576 tokens | 262,144 tokens |
| Model class | Reasoning | General text |
| Tokenizer | o200k_base (exact, public) | Proprietary (counts estimated) |
Count tokens for each model on its own page: GPT-5.5 Pro token counter and Mistral Medium 3.5 token counter. All OpenAI models are on the OpenAI Token Counter. All Mistral models are on the Mistral Token Counter.
FAQ
GPT-5.5 Pro vs Mistral Medium 3.5 FAQ
Which is cheaper, GPT-5.5 Pro or Mistral Medium 3.5?
Mistral Medium 3.5 is cheaper. At rates checked 2026-08-11, GPT-5.5 Pro costs $30.00 input / $180.00 output per 1M tokens, while Mistral Medium 3.5 costs $1.50 input / $7.50 output — about a 23x difference on a typical 3:1 input-heavy workload.
How much does a real request cost on GPT-5.5 Pro vs Mistral Medium 3.5?
A request with 10,000 input tokens and 2,000 output tokens costs about $0.66 on GPT-5.5 Pro and $0.03 on Mistral Medium 3.5. At 100,000 such requests per month that is $66,000 vs $3,000 — a difference of $63,000 per month.
Which has the bigger context window, GPT-5.5 Pro or Mistral Medium 3.5?
GPT-5.5 Pro. It supports 1,047,576 tokens of context versus 262,144 tokens — roughly 786,000 English words in one request.
Do GPT-5.5 Pro and Mistral Medium 3.5 count tokens the same way?
Not exactly. GPT-5.5 Pro uses the published o200k_base tokenizer and Mistral Medium 3.5 uses a proprietary tokenizer (counts are estimates). The same prompt will tokenize differently, which shifts effective cost per word.