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GPT-5.2 vs Mistral Magistral Small 2509

GPT-5.2 (2025) and Mistral Magistral Small 2509 (2025) are frontier reasoning models from OpenAI and MistralAI. GPT-5.2 ships a 256K-token context window, while Mistral Magistral Small 2509 ships a not-yet-sourced context window. On pricing, Mistral Magistral Small 2509 costs $0.5/1M input tokens versus $1.75/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.

Mistral Magistral Small 2509 is ~250% cheaper at $0.5/1M; pay for GPT-5.2 only for coding workflow support.

Specs

Released2025-12-112025-09-01
Context window256K
Parameters
Architecturedecoder only-
LicenseProprietaryProprietary
Knowledge cutoff--

Pricing and availability

GPT-5.2Mistral Magistral Small 2509
Input price$1.75/1M tokens$0.5/1M tokens
Output price$14/1M tokens$1.5/1M tokens
Providers

Capabilities

GPT-5.2Mistral Magistral Small 2509
Vision
Multimodal
Reasoning
Function calling
Tool use
Structured outputs
Code execution

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: GPT-5.2, multimodal input: GPT-5.2, reasoning mode: GPT-5.2, function calling: GPT-5.2, tool use: GPT-5.2, structured outputs: GPT-5.2, and code execution: GPT-5.2. Both models share the core language-model surface, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, GPT-5.2 lists $1.75/1M input and $14/1M output tokens, while Mistral Magistral Small 2509 lists $0.5/1M input and $1.5/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Mistral Magistral Small 2509 lower by about $4.63 per million blended tokens. Availability is 2 providers versus 1, so concentration risk also matters.

Choose GPT-5.2 when coding workflow support and broader provider choice are central to the workload. Choose Mistral Magistral Small 2509 when provider fit and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions.

FAQ

Which is cheaper, GPT-5.2 or Mistral Magistral Small 2509?

Mistral Magistral Small 2509 is cheaper on tracked token pricing. GPT-5.2 costs $1.75/1M input and $14/1M output tokens. Mistral Magistral Small 2509 costs $0.5/1M input and $1.5/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is GPT-5.2 or Mistral Magistral Small 2509 open source?

GPT-5.2 is listed under Proprietary. Mistral Magistral Small 2509 is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, GPT-5.2 or Mistral Magistral Small 2509?

GPT-5.2 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-5.2 or Mistral Magistral Small 2509?

GPT-5.2 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for reasoning mode, GPT-5.2 or Mistral Magistral Small 2509?

GPT-5.2 has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run GPT-5.2 and Mistral Magistral Small 2509?

GPT-5.2 is available on Replicate API and OpenRouter. Mistral Magistral Small 2509 is available on AWS Bedrock. Provider coverage can affect latency, region availability, compliance posture, and fallback options. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Continue comparing

Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.