API cost decision in 10 seconds

o3 Mini vs NewMistral Medium 3.5

Pick o3 Mini for lower cost; pick Mistral Medium 3.5 only if the larger context window matters more.

Page updated: 2026-05-26T15:08:08Z Data confirmed: 2026-05-27T02:08:17Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick o3 Mini for lower cost; pick Mistral Medium 3.5 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, o3 Mini is estimated at $3.3 vs $5.25 for Mistral Medium 3.5, saving $1.95 (37.1% lower).

Cost-first picko3 Mini

Context-first pickMistral Medium 3.5

Sample savings$1.9537.1%

10x traffic gap$19.5

Mistral Medium 3.5 has more context, but o3 Mini saves $1.95 on the standard workload. At 10x that traffic, the same price gap is about $19.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

o3 Mini stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	o3 Mini	Mistral Medium 3.5
Input-heavy / RAG	5M input + 500K output	o3 Mini	$7.7	$11.25
Balanced workload	1M input + 1M output	o3 Mini	$5.5	$9
Output-heavy chatbot	1M input + 5M output	o3 Mini	$23.1	$39

Cheaper input o3 Mini $1.1 vs $1.5 / 1M

o3 Mini is $0.4 cheaper per 1M input tokens (26.7% lower; 1.36x difference).

Cheaper output o3 Mini $4.4 vs $7.5 / 1M

o3 Mini is $3.1 cheaper per 1M output tokens (41.3% lower; 1.7x difference).

Larger context Mistral Medium 3.5 200K vs 262.14K

Mistral Medium 3.5 has 62.14K more context (1.31x larger).

Sample workload o3 Mini $3.3 vs $5.25

o3 Mini is $1.95 cheaper on the standard workload (37.1% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

o3 Mini Calculating… Estimated API cost

Mistral Medium 3.5 Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

o3 Mini has the lower input price; o3 Mini has the lower output price; Mistral Medium 3.5 offers the larger context window. For the 1M input plus 500K output sample, o3 Mini is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $3.3 for o3 Mini and $5.25 for Mistral Medium 3.5.

Best Fit

Choose o3 Mini when you care most about lower input-token price, and lower output-token price.

Choose Mistral Medium 3.5 when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, o3 Mini is estimated at $3.3 vs $5.25 for Mistral Medium 3.5, saving $1.95 (37.1% lower).
o3 Mini is $1.95 cheaper on the standard workload (37.1% lower).
o3 Mini is $0.4 cheaper per 1M input tokens (26.7% lower; 1.36x difference).
o3 Mini is $3.1 cheaper per 1M output tokens (41.3% lower; 1.7x difference).
Mistral Medium 3.5 has 62.14K more context (1.31x larger).

Head-to-Head Specs

Feature	o3 Mini (OpenAI)	NewMistral Medium 3.5 (Mistral)
Input Price prompt tokens per 1M	$1.1	$1.5
Completion Price per 1M tokens	$4.4	$7.5
Sample Workload Cost 1M input + 500K output	$3.3	$5.25
Context Window	200K	262.14K
Release Date	2025-01-31	2026-04-30
Popularity	#117	#125

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	o3 Mini	On the standard 1M input plus 500K output workload, o3 Mini is estimated at $3.3 vs $5.25 for Mistral Medium 3.5, saving $1.95 (37.1% lower).
High-volume input processing	o3 Mini	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	o3 Mini	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Mistral Medium 3.5	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

gpt-oss-120b (free) can replace o3 Mini when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace o3 Mini when lower sample workload cost matters most: $0.
gpt-oss-20b can replace o3 Mini when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace o3 Mini when lower sample workload cost matters most: $0.13.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.

Popular competitors

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Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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OpenAI catalog

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Mistral catalog

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Open Mistral models

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