Mistral Medium 3.5 vs o4-mini
Mistral AI against OpenAI, costed on the same three workloads. o4-mini is cheaper on all three workloads.
o4-mini has been retired by its vendor. Its column shows the last rates it was sold at, kept for reference.
Run this comparison on your own numbers
Monthly bill, side by side
| Workload | Mistral Medium 3.5 | o4-mini | Difference |
|---|---|---|---|
| Support chatbot 2,500 six-turn conversations a day |
$6,041 | $3,985 | $2,057 (1.5×) |
| Document summarizer 1,000 single-shot summaries a day |
$729 | $508 | $221 (+43%) |
| Coding agent 200 twelve-turn sessions a day |
$4,212 | $2,891 | $1,321 (+46%) |
No prompt caching and no batch discount on either side, so the comparison is like for like. Both figures assume 30 days a month.
The rate cards
| Mistral Medium 3.5 | o4-mini | |
|---|---|---|
| Input, per 1M tokens | $1.5 | $1.1 |
| Output, per 1M tokens | $7.5 | $4.4 |
| Cached input | $0.15 | $0.275 |
| Context window | 262K | 200K |
| Maximum output | 262K | 100K |
| Reasoning model | no | yes |
| Vision | yes | yes |
Beyond the price
- Mistral Medium 3.5 reads up to 262K tokens of context in one request; o4-mini stops at 200K.
- Mistral Medium 3.5 can write up to 262K tokens in one response, against 100K for o4-mini.
- Only o4-mini is a reasoning model, so its output bill also pays for the thinking it does before it answers.
- Cached input costs 90% less than fresh input on Mistral Medium 3.5 and 75% less on o4-mini, which matters most for workloads that resend the same prompt.
Run this comparison on your own numbers
Full detail: Mistral Medium 3.5 pricing · o4-mini pricing
More comparisons
Other head-to-heads that include Mistral Medium 3.5 or o4-mini.
- Mistral Medium 3.5 vs Nova 2 Pro
- Mistral Medium 3.5 vs Claude Haiku 4.5
- Mistral Medium 3.5 vs Command A
- o4-mini vs Nova 2 Lite
- o4-mini vs Nova 2 Pro
- o4-mini vs Claude Haiku 4.5
Common questions
Which is cheaper, Mistral Medium 3.5 or o4-mini?
o4-mini is cheaper on all three workloads.
How much would Mistral Medium 3.5 and o4-mini cost each month?
On PromptSpend's standard workloads, per month: support chatbot: Mistral Medium 3.5 $6,041, o4-mini $3,985 (o4-mini is cheaper by $2,057); document summarizer: Mistral Medium 3.5 $729, o4-mini $508 (o4-mini is cheaper by $221); coding agent: Mistral Medium 3.5 $4,212, o4-mini $2,891 (o4-mini is cheaper by $1,321). No prompt caching and no batch discount is assumed.
How do Mistral Medium 3.5 and o4-mini differ apart from price?
Mistral Medium 3.5 reads up to 262K tokens of context in one request; o4-mini stops at 200K. Mistral Medium 3.5 can write up to 262K tokens in one response, against 100K for o4-mini. Only o4-mini is a reasoning model, so its output bill also pays for the thinking it does before it answers. Cached input costs 90% less than fresh input on Mistral Medium 3.5 and 75% less on o4-mini, which matters most for workloads that resend the same prompt.