Mistral Medium 3.5 vs o3-mini

Mistral Medium 3.5 vs o3-mini: o3-mini is cheaper for input-heavy usage ($1.10/M vs $1.50/M input tokens), while o3-mini is better for long-context tasks (500,000 tokens).

Direct answer: choose o3-mini for lower token spend and choose o3-mini when your workload needs longer context.

Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.

Mistral AI

Mistral Medium 3.5

OpenAI

o3-mini

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Mistral Medium 3.5 pricing page o3-mini pricing page Mistral AI provider overview OpenAI provider overview

Cost Comparison (1000 input + 500 output tokens, 100 requests/day)

Mistral Medium 3.5

Per Request:$0.005250

Daily:$0.525

Monthly:$15.75

Yearly:$191.625

o3-mini

Per Request:$0.003300

Daily:$0.33

Monthly:$9.90

Yearly:$120.45

Cost Differences

$0.001950

Per Request

$0.195

Daily

$5.85

Monthly

$71.175

Yearly

o3-mini costs less than Mistral Medium 3.5

Quick Recommendation

Winner for direct API pricing: o3-mini. At the default workload, o3-mini saves about $5.85/month ($71.175/year) versus Mistral Medium 3.5.

Mistral Medium 3.5 full pricing breakdown o3-mini full pricing breakdown Mistral AI API pricing details OpenAI API pricing details Mistral AI vs OpenAI API pricing Codex Mini vs o4-mini Deep Research Codex Mini vs o3 Deep Research

Feature Comparison

Feature	Mistral Medium 3.5	o3-mini
Provider	Mistral AI	OpenAI
Input Price	$1.50/1M tokens	$1.10/1M tokens
Output Price	$7.50/1M tokens	$4.40/1M tokens
Context Window	256,000 tokens	500,000 tokens
Max Output	32,768 tokens	65,536 tokens
Category	flagship	reasoning
Capabilities	textvisioncodereasoning	textreasoningcode
Release Date	4/29/2026	1/31/2025

Mistral Medium 3.5 vs o3-mini: Which Should You Choose?

Choosing between Mistral Medium 3.5 and o3-mini depends on your priorities: cost efficiency, context length, or raw capability. o3-mini is the more affordable option at $1.10/1M input tokens — 27% cheaper than Mistral Medium 3.5. Meanwhile, o3-mini offers a significantly larger context window at 500,000 tokens vs 256,000 for Mistral Medium 3.5.

These models come from different providers — Mistral AI and OpenAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Mistral AI, switching to OpenAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.

These models target different tiers: Mistral Medium 3.5 is a flagship model while o3-mini is reasoning. This means they're optimized for different workloads. Mistral Medium 3.5 is built for complex tasks that require deeper reasoning, while o3-mini offers better value for routine operations.

Output costs matter too. Mistral Medium 3.5 charges $7.50/1M output tokens vs $4.40 for o3-mini. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. o3-mini has the edge here at $4.40/1M output tokens.

Multimodal capabilities: Mistral Medium 3.5 supports vision (image inputs) while o3-mini is text-only. If your application needs image understanding, this narrows your choice.

Best Use Cases

Choose Mistral Medium 3.5 when:

• You need more capabilities (vision)
• You're already using Mistral AI's API ecosystem

Choose o3-mini when:

• Budget is a primary concern
• You need a larger context window (500,000 tokens)
• You need longer outputs (up to 65,536 tokens)
• You're already using OpenAI's API ecosystem

Pros and Caveats at a Glance

Mistral Medium 3.5

• Input pricing: $1.50/M tokens
• Output pricing: $7.50/M tokens
• Context window: 256,000 tokens
• Max output: 32,768 tokens

Watch out for

• Higher input cost than o3-mini
• Higher output cost than o3-mini
• Smaller context window than o3-mini

o3-mini

• Input pricing: $1.10/M tokens
• Output pricing: $4.40/M tokens
• Context window: 500,000 tokens
• Max output: 65,536 tokens

Watch out for

• Trade-offs are minor in this matchup.

Try Different Scenarios

Use the calculator below to see how costs change with different usage patterns

Mistral Medium 3.5 (Mistral AI)

Cost Calculator

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Model

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o3-mini (OpenAI)

Cost Calculator

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Model

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Start using Mistral Medium 3.5 today

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Frequently Asked Questions

Which is cheaper, Mistral Medium 3.5 or o3-mini?▼

o3-mini is cheaper for input tokens at $1.10 per million tokens vs $1.50 for Mistral Medium 3.5 — that's 27% savings on input costs.

What is the context window difference between Mistral Medium 3.5 and o3-mini?▼

Mistral Medium 3.5 supports 256,000 tokens while o3-mini supports 500,000 tokens — a difference of 244,000 tokens in favor of o3-mini.

Which model is better for AI Agent / Agentic Workflows?▼

Both models support text, code, reasoning. For ai agent / agentic workflows, o3-mini is the lower-cost option, while o3-mini offers a larger context window (500,000 vs 256,000 tokens). Choose o3-mini for budget sensitivity or o3-mini for longer context tasks.

Which model has better overall pricing for heavy usage?▼

At 100 requests/day with 1,000 input and 500 output tokens each, Mistral Medium 3.5 costs about $15.75/month and o3-mini costs about $9.90/month. Overall, o3-mini has lower combined input + output rates ($1.10 in, $4.40 out) vs Mistral Medium 3.5.

Where can I compare Mistral AI and OpenAI API pricing beyond this model matchup?▼

See the Mistral AI vs OpenAI provider comparison page for lineup-level averages, then review each model page for exact per-token rates.