Mistral Medium 3.5
Mistral Medium 3.5 is worth evaluating for coding, rag, and agents when its provider route and context window match the workload.
Use it for
- Teams evaluating coding, rag, and agents
- Workloads that can use a 262k context window
- Buyers comparing 3 tracked provider routes
Do not use it for
- Workloads where another current model has stronger sourced task evidence
- Family
- Mistral Medium
- Released
- 2026-04-29
- Context
- 262k
- Parameters
- 128B
- Architecture
- Decoder Only
- Specialization
- general
- Openness
- Open weights
- License
- Mistral Modified MIT LicenseCommercial use: conditional
- Weights
- Available
- Code
- Unknown
- Training
- Pretrained
Cheapest of 3 routes · Mistral AI Studio
About
Mistral's 128B flagship merged model, released April 29, 2026. Open weights available on HuggingFace since ~May 22, 2026 under a Modified MIT License (free for companies with <$20M/month revenue). Dense 128B architecture with 256k context window, configurable reasoning effort, vision encoder for variable image sizes, and native function calling. Achieves 91.4% on τ³-Telecom and 77.6% on SWE-Bench Verified. Strong multilingual support across 24+ languages. Replaces Mistral Medium 3.1, Magistral, and Devstral 2 as Mistral's primary merged model. Available via Mistral API at $1.50/$7.50 per million tokens (input/output) and via NVIDIA NIM/endpoints.
Top use-case fit: coding, agents, and build tasks
Coding
Q/$ D1 relevant benchmark in the decision map.
RAG
Included by capability and metadata signals in the decision map.
Agents
Q/$ C2 relevant benchmarks in the decision map.
Provider price ladder
Compare all 3Compare API pricing across 3 providers for input and output tokens, batch, and cached reads when available.
| Provider | Input / 1M | Output / 1M | Route |
|---|---|---|---|
| Mistral AI Studio | $1.50 | $7.50 | Serverless |
| OpenRouter | $1.50 | $7.50 | Serverless |
| Vercel AI Gateway | $1.50 | $7.50 | Serverless |
Available via routers & gateways(10)
LiteLLM
GatewayOpen-source Python SDK and proxy server that unifies 100+ LLM APIs behind a single OpenAI-compatible interface, with load balancing, cost tracking, and configurable failover.
OpenRouter
HybridUnified hybrid gateway to 400+ models from 60+ providers via a single OpenAI-compatible API, with optional auto-routing that selects the best model per prompt.
Portkey
GatewayProduction AI gateway routing to 1,600+ LLMs with failover, load balancing, semantic caching, and guardrails; Apache 2.0 core is fully self-hostable with the complete feature set.
AIRouter
RouterCommercial LLM router that analyzes incoming requests and routes to the optimal model for cost/quality/latency via a drop-in OpenAI-compatible API, with a privacy-preserving embedding mode that avoids sending prompt content.
Martian
RouterAI-powered LLM router that analyzes each prompt in real-time to select the optimal model, targeting 20–97% cost reduction while maintaining quality; San Francisco startup reportedly nearing $1.3B valuation.
Neutrino AI
RouterCommercial LLM router that dynamically routes each query to the best-suited model with load balancing and fallback handling, charging 3% of underlying AI spend.
Capabilities
Benchmark peer barsfor Coding
Benchmark scores(4)
| Benchmark | Score | Version | Evaluation | Source |
|---|---|---|---|---|
| SWE-bench Verified | 77.6 | SWE-bench VerifiedObserved 2026-04-30 | — | Source |
| Google-Proof Q&A | 71.3 | —Observed 2026-04-29 | — | Source |
| MMLU PRO | 79.8 | —Observed 2026-04-29 | — | Source |
| τ-bench | 91.4 | τ³-Telecom (agentic tool use) (accuracy)Observed 2026-06-07 | — | Source |
Migration checks
No linked migration route is available for this model yet.
Compare Mistral Medium 3.5 with other models
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- Mistral Medium 3.5 vs Claude Mythos Preview144
- Mistral Medium 3.5 vs Magistral Small 250659
- Mistral Medium 3.5 vs Codex 135
- Mistral Medium 3.5 vs Qwen3.5-397B-A17B26
- Mistral Medium 3.5 vs Phi-4 Mini Flash Reasoning16
- Mistral Medium 3.5 vs Phi-4 Reasoning Vision 15B16
- Mistral Medium 3.5 vs Claude 1.313
Comparison and alternatives
Browse all comparisons →Show all 2 popular comparisonssorted by 7-day search impressions
Cheapest of 3 routes · Mistral AI Studio