Gemma 3 12B Instruct vs Mistral Medium 3.5
Gemma 3 12B Instruct (2025) and Mistral Medium 3.5 (2026) are frontier reasoning models from Google DeepMind and MistralAI. Gemma 3 12B Instruct ships a 128k-token context window, while Mistral Medium 3.5 ships a 262k-token context window. On pricing, Gemma 3 12B Instruct costs $0.20/1M input tokens versus $1.50/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Gemma 3 12B Instruct is ~650% cheaper at $0.20/1M; pay for Mistral Medium 3.5 only for reasoning depth.
Decision scorecard
Local evidence first| Signal | Gemma 3 12B Instruct | Mistral Medium 3.5 |
|---|---|---|
| Best for | general production evaluation | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Long context | Coding, RAG, and Agents |
| Context window | 128k | 262k |
| Cheapest output | $0.20/1M tokens | $7.50/1M tokens |
| Provider routes | 1 tracked | 3 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- Gemma 3 12B Instruct has the lower cheapest tracked output price at $0.20/1M tokens.
- Local decision data tags Gemma 3 12B Instruct for Long context.
- Mistral Medium 3.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Mistral Medium 3.5 has broader tracked provider coverage for fallback and procurement flexibility.
- Mistral Medium 3.5 uniquely exposes Vision, Multimodal, and Reasoning in local model data.
- Local decision data tags Mistral Medium 3.5 for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Gemma 3 12B Instruct
$210
Cheapest tracked route/tier: Fireworks AI
Mistral Medium 3.5
$3,075
Cheapest tracked route/tier: Mistral AI Studio
Estimated monthly gap: $2,865. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for Gemma 3 12B Instruct and Mistral Medium 3.5; plan for SDK, billing, or endpoint changes.
- Mistral Medium 3.5 is $7.30/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Mistral Medium 3.5 adds Vision, Multimodal, and Reasoning in local capability data.
- No overlapping tracked provider route is sourced for Mistral Medium 3.5 and Gemma 3 12B Instruct; plan for SDK, billing, or endpoint changes.
- Gemma 3 12B Instruct is $7.30/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Vision, Multimodal, and Reasoning before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-01-01 | 2026-04-29 |
| Context window | 128k | 262k |
| Parameters | 12B | 128B |
| Architecture | Decoder Only | Decoder Only |
| License | Gemma | Mistral License |
| Openness | Open weights | Open weights |
| Commercial use | Commercial use: conditional | Commercial use: non-commercial |
| Knowledge cutoff | 2024-08 | - |
Pricing and availability
| Pricing attribute | Gemma 3 12B Instruct | Mistral Medium 3.5 |
|---|---|---|
| Input price | $0.20/1M tokens | $1.50/1M tokens |
| Output price | $0.20/1M tokens | $7.50/1M tokens |
| Providers |
Capabilities
| Capability | Gemma 3 12B Instruct | Mistral Medium 3.5 |
|---|---|---|
| Vision | No | Yes |
| Multimodal | No | Yes |
| Reasoning | No | Yes |
| Function calling | No | Yes |
| Tool use | No | Yes |
| Structured outputs | No | Yes |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Deep dive
The capability footprint differs most on vision: Mistral Medium 3.5, multimodal input: Mistral Medium 3.5, reasoning mode: Mistral Medium 3.5, function calling: Mistral Medium 3.5, tool use: Mistral Medium 3.5, and structured outputs: Mistral Medium 3.5. 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, Gemma 3 12B Instruct lists $0.20/1M input and $0.20/1M output tokens on the cheapest tracked provider, while Mistral Medium 3.5 lists $1.50/1M input and $7.50/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemma 3 12B Instruct lower by about $3.10 per million blended tokens. Availability is 1 providers versus 3, so concentration risk also matters.
Choose Gemma 3 12B Instruct when provider fit and lower input-token cost are central to the workload. Choose Mistral Medium 3.5 when reasoning depth, larger context windows, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Gemma 3 12B Instruct or Mistral Medium 3.5?
Mistral Medium 3.5 supports 262k tokens, while Gemma 3 12B Instruct supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Gemma 3 12B Instruct or Mistral Medium 3.5?
Gemma 3 12B Instruct is cheaper on tracked token pricing. Gemma 3 12B Instruct costs $0.20/1M input and $0.20/1M output tokens. Mistral Medium 3.5 costs $1.50/1M input and $7.50/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Gemma 3 12B Instruct or Mistral Medium 3.5 open source?
Gemma 3 12B Instruct is listed under Gemma. Mistral Medium 3.5 is listed under Mistral License. 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, Gemma 3 12B Instruct or Mistral Medium 3.5?
Mistral Medium 3.5 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.
Which is better for multimodal input, Gemma 3 12B Instruct or Mistral Medium 3.5?
Mistral Medium 3.5 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.
Where can I run Gemma 3 12B Instruct and Mistral Medium 3.5?
Gemma 3 12B Instruct is available on Fireworks AI. Mistral Medium 3.5 is available on Mistral AI Studio, OpenRouter, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-06-17. Data sourced from public model cards and provider documentation.