GPT-5.4 Nano vs Mistral Magistral Small 2509
GPT-5.4 Nano (2026) and Mistral Magistral Small 2509 (2025) are general-purpose language models from OpenAI and MistralAI. GPT-5.4 Nano ships a 400K-token context window, while Mistral Magistral Small 2509 ships a not-yet-sourced context window. On pricing, GPT-5.4 Nano costs $0.2/1M input tokens versus $0.5/1M 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.
GPT-5.4 Nano is ~150% cheaper at $0.2/1M; pay for Mistral Magistral Small 2509 only for provider fit.
Decision scorecard
Local evidence first| Signal | GPT-5.4 Nano | Mistral Magistral Small 2509 |
|---|---|---|
| Decision fit | Coding, RAG, and Agents | General |
| Context window | 400K | — |
| Cheapest output | $1.25/1M tokens | $1.5/1M tokens |
| Provider routes | 2 tracked | 1 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- GPT-5.4 Nano has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-5.4 Nano has the lower cheapest tracked output price at $1.25/1M tokens.
- GPT-5.4 Nano has broader tracked provider coverage for fallback and procurement flexibility.
- GPT-5.4 Nano uniquely exposes Multimodal, Function calling, and Tool use in local model data.
- Local decision data tags GPT-5.4 Nano for Coding, RAG, and Agents.
- Use Mistral Magistral Small 2509 when your own prompt tests beat the comparison signals; the local data does not show a decisive standalone advantage yet.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output prices on this page.
GPT-5.4 Nano
$473
Cheapest tracked route: OpenAI API
Mistral Magistral Small 2509
$775
Cheapest tracked route: AWS Bedrock
Estimated monthly gap: $303. Batch, cache, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for GPT-5.4 Nano and Mistral Magistral Small 2509; plan for SDK, billing, or endpoint changes.
- Mistral Magistral Small 2509 is $0.25/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Multimodal, Function calling, and Tool use before moving production traffic.
- No overlapping tracked provider route is sourced for Mistral Magistral Small 2509 and GPT-5.4 Nano; plan for SDK, billing, or endpoint changes.
- GPT-5.4 Nano is $0.25/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- GPT-5.4 Nano adds Multimodal, Function calling, and Tool use in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-03-05 | 2025-09-01 |
| Context window | 400K | — |
| Parameters | — | — |
| Architecture | decoder only | - |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-08 | - |
Pricing and availability
| Pricing attribute | GPT-5.4 Nano | Mistral Magistral Small 2509 |
|---|---|---|
| Input price | $0.2/1M tokens | $0.5/1M tokens |
| Output price | $1.25/1M tokens | $1.5/1M tokens |
| Providers |
Capabilities
| Capability | GPT-5.4 Nano | Mistral Magistral Small 2509 |
|---|---|---|
| Vision | No | No |
| Multimodal | Yes | No |
| Reasoning | No | No |
| Function calling | Yes | No |
| Tool use | Yes | No |
| Structured outputs | Yes | No |
| Code execution | Yes | No |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on multimodal input: GPT-5.4 Nano, function calling: GPT-5.4 Nano, tool use: GPT-5.4 Nano, structured outputs: GPT-5.4 Nano, and code execution: GPT-5.4 Nano. 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-5.4 Nano lists $0.2/1M input and $1.25/1M 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 GPT-5.4 Nano lower by about $0.28 per million blended tokens. Availability is 2 providers versus 1, so concentration risk also matters.
Choose GPT-5.4 Nano when coding workflow support, lower input-token cost, and broader provider choice are central to the workload. Choose Mistral Magistral Small 2509 when provider fit 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-5.4 Nano or Mistral Magistral Small 2509?
GPT-5.4 Nano is cheaper on tracked token pricing. GPT-5.4 Nano costs $0.2/1M input and $1.25/1M 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-5.4 Nano or Mistral Magistral Small 2509 open source?
GPT-5.4 Nano 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 multimodal input, GPT-5.4 Nano or Mistral Magistral Small 2509?
GPT-5.4 Nano 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 function calling, GPT-5.4 Nano or Mistral Magistral Small 2509?
GPT-5.4 Nano has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for tool use, GPT-5.4 Nano or Mistral Magistral Small 2509?
GPT-5.4 Nano has the clearer documented tool use signal in this comparison. If tool use is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run GPT-5.4 Nano and Mistral Magistral Small 2509?
GPT-5.4 Nano is available on OpenAI API and OpenRouter. Mistral Magistral Small 2509 is available on AWS Bedrock. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.