o3 Paid vs 
Mistral Medium 3.5 (batch) Open
o3 vs Mistral Medium 3.5 (batch) compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.
Prices & specs refreshed from live data · olud.ai
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
$8 /M outputManaged API (no infra to run)
$3.75 /M outputNo per-token fees if you self-host
o3 vs Mistral Medium 3.5 (batch) specs
| Spec | o3 | Mistral Medium 3.5 (batch) | Winner |
|---|---|---|---|
| Maker | OpenAI | Mistral AI | – |
| Type | Proprietary | Open-weight | |
| Context window | 200K tokens | 262K tokens | |
| Input price | $2/M | $0.75/M · free self-host | |
| Output price | $8/M | $3.75/M · free self-host | |
| Vision / multimodal | Yes | Yes | = Tie |
| Tool / function calling | Yes | Yes | = Tie |
| Self-hostable | No (API only) | Yes | |
| License | Proprietary | Apache 2.0 |
Price gap & when to choose each
Mistral Medium 3.5 (batch) is ~2.1× cheaper than o3 on output tokens ($3.75 vs $8 per M tokens).
- You want frontier performance through a managed API
- You value reliability & ecosystem
- You don't want to manage infrastructure
- You want to self-host or run on your cloud
- You need the longer 262K context window
- You prioritize data privacy & control
- You want the lowest operating costs
- You are building open or reproducible AI
Feature comparison
| Capability | o3 | Mistral Medium 3.5 (batch) |
|---|---|---|
| Open weights (downloadable) | ✗ | ✓ |
| Self-hostable | ✗ | ✓ |
| Runs fully offline | ✗ | ✓ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✗ | ✗ |
Benchmarks: o3 vs Mistral Medium 3.5 (batch)
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How o3 and Mistral Medium 3.5 (batch) score
| Criterion | o3 | Mistral Medium 3.5 (batch) |
|---|---|---|
| Cost-efficiency | 3.5 | 4.0 |
| Context window | 4.0 | 4.0 |
| Openness | 1.5 | 5.0 |
| Self-hosting | 1.0 | 5.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
o3 Paid
o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following....
Mistral Medium 3.5 (batch) Open
Mistral Medium 3.5 is a dense 128B instruction-following model from Mistral AI. It supports text and image inputs with text output, and is designed for agentic workflows, coding, and complex...
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
Is Mistral Medium 3.5 (batch) as good as o3?
Mistral Medium 3.5 (batch) is open-weight and competitive on many tasks, but o3 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.
Can I run Mistral Medium 3.5 (batch) locally?
Yes. Mistral Medium 3.5 (batch) has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. o3 is API-only and cannot be self-hosted.
How much cheaper is Mistral Medium 3.5 (batch)?
Mistral Medium 3.5 (batch) costs $3.75/M output vs $8/M for o3 — roughly 2x cheaper via API, and free if you self-host.
o3 vs Mistral Medium 3.5 (batch) — which should I pick in 2026?
Choose Mistral Medium 3.5 (batch) if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose o3 if you want frontier capability through a managed API with zero infrastructure to run.
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