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Mistral: Mistral Medium 3.5 vs o3: API Cost Comparison

Compare the API pricing, context windows, features, and real-world cost projections for Mistral: Mistral Medium 3.5 (Mistral AI) and o3 (OpenAI). Use the interactive calculator below to compute your exact monthly cost based on your token usage and request volume.

Prices verified May 6, 2026

Interactive Cost Calculator

Mistral AIMistral: Mistral Medium 3.5OpenAIo3

Fills in typical token counts for a workload type

Tokens in each prompt sent to the model

Tokens generated in each response

Total API calls per month

Showing costs for 2 models. Cheapest: Mistral: Mistral Medium 3.5 at $52.50/month.

Cheapest: Mistral: Mistral Medium 3.5 at $52.50/mo — save 12.5% vs o3
Alert
BestMistral: Mistral Medium 3.5
Mistral AI$52.50$0.005250$15.00$37.5012.5%Alerts coming soon
o3
OpenAI$60.00$0.006000$20.00$40.00Alerts coming soon

Monthly Cost Comparison

Price Comparison at a Glance

All prices are in USD per 1 million tokens ($/M tokens). Lower is cheaper.

Pricing TypeMistral: Mistral Medium 3.5o3Cheaper
Input (standard)$1.50/M$2.00/MMistral: Mistral Medium 3.5
Output$7.50/M$8.00/MMistral: Mistral Medium 3.5
Cached inputN/A$0.50/M

Prices last verified: 2026-03-06 – 2026-05-06

Cost Breakdown by Usage Volume

Estimated monthly costs at different request volumes, assuming 1,000 input tokens and 500 output tokens per request. Adjust in the calculator above for your specific use case.

VolumeMistral: Mistral Medium 3.5Monthlyo3MonthlyMistral: Mistral Medium 3.5Per requesto3Per request
1K requests/mo$5.25$6.00$0.005250$0.006000
10K requests/mo$52.50$60.00$0.005250$0.006000
100K requests/mo$525.00$600.00$0.005250$0.006000
1M requests/mo$5,250.00$6,000.00$0.005250$0.006000

Green values indicate the lower-cost option at each volume tier. Cost per request is calculated at 1,000 input + 500 output tokens using standard (non-batch, non-cached) pricing.

Price History

Input price per 1M tokens

When to Choose Mistral: Mistral Medium 3.5

by Mistral AI

  • General chatbot

Input / 1M tokens

$1.50/M

Output / 1M tokens

$7.50/M

Context window

262,144

Tier

mid

When to Choose o3

by OpenAI

  • Code generation
  • Document summarization

Input / 1M tokens

$2.00/M

Output / 1M tokens

$8.00/M

Context window

200,000

Tier

reasoning

Key Differences Beyond Price

Cost is only one factor in choosing an AI model. Context window size, rate limits, supported features, and latency all affect whether a model fits your use case.

CapabilityMistral: Mistral Medium 3.5o3
Context window262,144 tokens200,000 tokens
Max output tokens4,096 tokens100,000 tokens
Performance tierMidReasoning
Vision / image inputYesYes
Function callingYesYes
JSON modeYesYes
Prompt cachingNoYes
Batch API (50% discount)NoNo
Extended reasoningYesYes
Fine-tuningNoNo
Rate limit (req/min)Not published1,000

o3 notes

State-of-the-art reasoning performance. Costs reflect internal thinking tokens. Price reduced significantly from launch.

Frequently Asked Questions

Is Mistral: Mistral Medium 3.5 cheaper than o3?

At standard usage (1,000 input tokens, 500 output tokens, 100,000 requests/month), Mistral: Mistral Medium 3.5 costs $525.00/month versus $600.00/month for o3 — a 13% saving. Your actual savings will vary based on your token profile; output-heavy workloads amplify differences in output pricing.

Which model has a larger context window, Mistral: Mistral Medium 3.5 or o3?

Mistral: Mistral Medium 3.5 has a larger context window at 262,144 tokens, compared to 200,000 tokens for o3. A larger context window is important for processing long documents, multi-turn conversations, or large codebases without truncation.

Do Mistral: Mistral Medium 3.5 and o3 support the Batch API?

Neither Mistral: Mistral Medium 3.5 nor o3 currently supports a batch API with discounted pricing. For batch-eligible alternatives, consider models from OpenAI, Anthropic, or Google that include batch API support.

Which model offers better prompt caching?

o3 supports prompt caching at $0.50/M for cached input, while Mistral: Mistral Medium 3.5 does not offer prompt caching. For RAG applications or chatbots with large, repeated context, o3's caching capability can substantially reduce effective costs.

What are the best use cases for Mistral: Mistral Medium 3.5 vs o3?

Mistral: Mistral Medium 3.5 is best suited for General chatbot, while o3 is optimized for Code generation, Document summarization. Choose based on which use case matches your primary workload — and validate with the cost calculator above to confirm the total monthly spend fits your budget.

What is the cost per request for Mistral: Mistral Medium 3.5 vs o3?

At 1,000 input tokens and 500 output tokens per request — a typical conversational workload — Mistral: Mistral Medium 3.5 costs $0.005250 per request and o3 costs $0.006000 per request. At 100,000 requests/month, that translates to $525.00 and $600.00 respectively. Use the interactive calculator to adjust these parameters for your actual workload.

Mistral: Mistral Medium 3.5 vs o3: Summary

When comparing Mistral: Mistral Medium 3.5 and o3 for API cost, the right choice depends on your workload's token profile, required features, and tolerance for latency. Mistral: Mistral Medium 3.5 offers lower total cost at standard usage volumes (1,000 input + 500 output tokens per request at 100,000 requests/month) at $525.00/month, compared to $600.00/month for o3.

Both models are priced in USD per million tokens, the standard unit across all major AI API providers. Mistral: Mistral Medium 3.5 charges $1.50/M for input tokens and $7.50/M for output tokens. o3 charges $2.00/M input and $8.00/M output. If your workload is output-heavy (more tokens generated than consumed as input), the model with the lower output price compounds cost savings significantly at scale.

Prompt caching is supported by o3 but not Mistral: Mistral Medium 3.5. For workloads with large, repeated system prompts or document context — such as RAG pipelines or multi-turn conversations with a fixed knowledge base — prompt caching can reduce effective input costs by 60–90%, which may change the cost ranking between these two models at your specific usage pattern.

Context window capacity differs between the two: Mistral: Mistral Medium 3.5 supports up to 262,144 tokens in a single request, versus 200,000 tokens for o3. A larger context window is essential for document summarization, large codebase analysis, and multi-document retrieval-augmented generation (RAG) applications.

Use the interactive calculator at the top of this page to enter your actual token usage and monthly request volume for a precise cost comparison tailored to your workload. Adjust for batch API discounts and prompt caching to find the most cost-effective option for your specific deployment.

Explore other model comparisons from the same providers or performance tiers.

Related Provider Pages

View complete pricing tables and model lineups for the providers behind these models.

Relevant Use Cases

See cost recommendations for workloads where Mistral: Mistral Medium 3.5 or o3 is recommended.