Back to Text & reasoning

Model comparison

GPT-6 Astra vs Mistral Medium 3.5

Compare GPT-6 Astra and Mistral Medium 3.5 using the same provider-sourced text & reasoning rubric. No mystery score and no invented benchmark ranking.

Facts checked September 4, 2026

Estimate your cost

Set your usage. Your estimate updates as you type.

Example: 6,000 input tokens for 10 pages, plus a 500-token summary. Page lengths vary; adjust the numbers below.

One run sends your input to the model once and receives an answer. Tokens are pieces of text: input is what you send, output is the answer you receive.

Advanced options
How this estimate works

Estimates exclude taxes, tools, cache storage/writes, free allowances and custom discounts. Image estimates cover output only, not prompt or reference-image charges. Quality modes differ by model. Unlisted settings are not treated as free.

Estimate your cost
ModelEstimated total (USD)
GPT-6 AstraOpenAI$0.085
Mistral Medium 3.5Mistral AINo reviewed rate

Quick take

GPT-6 Astra

OpenAI's most capable model for difficult end-to-end work, combining frontier reasoning with a million-token context window and a broad set of agent tools.

Best for

  • Complex, long-running agent workflows
  • Repository-scale coding and computer use
  • Research and document creation with several tools

Watch out for

Access is still rolling out, fine-tuning is not supported, and requests above 272K input tokens use higher rates across the full request. Confirm access and measure total task cost before standardizing on Astra.

Mistral Medium 3.5

Mistral's open-weight frontier model for demanding multimodal, coding, reasoning, and agent workflows, with a 256K context window.

Best for

  • Complex coding and agent workflows
  • Multimodal document and image reasoning
  • Organizations choosing between hosted and controlled deployment

Watch out for

The headline token price applies to Mistral's standard hosted endpoint. Regional inference costs more, and self-hosting shifts the bill to GPUs, operations, and support.

Compare the published facts

GPT-6 Astra vs Mistral Medium 3.5

Values use each provider's own published units and limits. A blank means the provider did not publish a directly comparable value in the sources reviewed.

Text & reasoningGPT-6 AstraMistral Medium 3.5
Context windowMaximum combined prompt and working context documented by the provider.1.05M tokens256K tokens combined
Maximum outputProvider-published response limit, where available.128K tokensNot separately published
Knowledge cutoffLatest reliable knowledge date explicitly published by the model provider. Search and connected tools can retrieve newer information but do not change the model's built-in cutoff.April 30, 2026Not published
Input priceCurrent standard list price per million input tokens unless noted.$10 / 1M$1.50 / 1M
Output priceCurrent standard list price per million output tokens unless noted.$50 / 1M$7.50 / 1M
InputsMedia types accepted by the listed model endpoint.Text, imageText, image
Tools & agentsSelected native tools and agent-building capabilities, not an exhaustive list.Functions, search, code, computer, image, MCPFunctions, agents, built-in tools, structured and predicted outputs

How to choose

Compare the job, not the hype.

Start with the job you need to complete, then validate cost, access, and policy details on your exact provider route.

GPT-6 Astra

OpenAI says API content is not used for model training by default. Standard abuse-monitoring logs may be retained for up to 30 days, with additional controls available to qualifying organizations.

Mistral Medium 3.5

Mistral's commercial terms exclude model training by default except when a customer opts in or uses designated Labs or preview models. Standard API input and output retention is generally 30 rolling days for abuse monitoring unless zero data retention is enabled.

Frequently asked questions

GPT-6 Astra vs Mistral Medium 3.5 FAQ

What is the main difference between GPT-6 Astra and Mistral Medium 3.5?

GPT-6 Astra: OpenAI's most capable model for difficult end-to-end work, combining frontier reasoning with a million-token context window and a broad set of agent tools. Mistral Medium 3.5: Mistral's open-weight frontier model for demanding multimodal, coding, reasoning, and agent workflows, with a 256K context window.

Should I choose GPT-6 Astra or Mistral Medium 3.5?

Consider GPT-6 Astra when your priority is Complex, long-running agent workflows. Consider Mistral Medium 3.5 when your priority is Complex coding and agent workflows. Test both with your own data and provider route before committing.

Is this GPT-6 Astra vs Mistral Medium 3.5 comparison based on Cody benchmarks?

No. This comparison aligns provider-published facts for the Text & reasoning category. It does not claim a universal winner or combine incompatible third-party benchmark scores.