Neither wins outright: AionLabs: Aion 3.5 is the pick when you need to fit long inputs in one request, Mistral: Mistral Medium 3.1 (batch) when cost matters at scale.
| Spec | AionLabs: Aion 3.5 | Mistral: Mistral Medium 3.1 (batch) |
|---|---|---|
| Provider | Aion Labs | Mistral AI |
| Input price (per 1M tokens) | $3.00 | $0.20 |
| Output price (per 1M tokens) | $6.00 | $1.00 |
| Blended price (3:1 input/output) | $3.75 | $0.40 |
| Cheaper than … of all models we track | 17% | 58% |
| Context window | 262K tokens (~393 pages) | 131K tokens (~197 pages) |
| Larger context than … of all models | 48% | 23% |
| Max output per response | 33K tokens (~24,600 words) | 105K tokens (~78,600 words) |
| Input types | text | text, image, file |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2026-09-23 | 2025-08-13 |
Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.
| Workload (per month) | AionLabs: Aion 3.5 | Mistral: Mistral Medium 3.1 (batch) | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $345 | $35.00 | Mistral: Mistral Medium 3.1 (batch) saves $310 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $420 | $34.00 | Mistral: Mistral Medium 3.1 (batch) saves $386 |
| Coding / tool-using agent 2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens) | $432 | $36.00 | Mistral: Mistral Medium 3.1 (batch) saves $396 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $276 | $22.00 | Mistral: Mistral Medium 3.1 (batch) saves $254 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $156 | $11.00 | Mistral: Mistral Medium 3.1 (batch) saves $145 |
| Capability | AionLabs: Aion 3.5 | Mistral: Mistral Medium 3.1 (batch) | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | ✓ Yes | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | ✓ Yes | return JSON that validates against your schema |
| Reasoning / thinking mode | ✓ Yes | — | spend extra tokens thinking before answering hard problems |
| Image input | — | ✓ Yes | read screenshots, charts and scanned pages |
| Audio input | — | — | take speech or audio directly |
| File / PDF input | — | ✓ Yes | accept documents without your own parsing step |
| Image output | — | — | generate images, not just text |
| Built-in web search | — | — | answer from live web results |
| Seed (reproducible sampling) | — | ✓ Yes | repeat a generation for tests and evals |
| Log-probabilities | — | — | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
| Date | Model | Input / 1M | Output / 1M |
|---|---|---|---|
| 2026-09-10 | Mistral: Mistral Medium 3.1 (batch) | $0.20 | $1.00 |
Neither wins outright: AionLabs: Aion 3.5 is the pick when you need to fit long inputs in one request, Mistral: Mistral Medium 3.1 (batch) when cost matters at scale. In short: AionLabs: Aion 3.5 when you need to fit long inputs in one request, you need reasoning / thinking mode, you want the newer model; Mistral: Mistral Medium 3.1 (batch) when cost matters at scale, you need image input, you need file / PDF input, you need seed (reproducible sampling), you generate long outputs in one go.
Mistral: Mistral Medium 3.1 (batch) is cheaper: $0.40 vs $3.75 per 1M tokens at a typical 3:1 input/output mix, 89% less. For 50,000 support conversations a month that is $35.00 against $345.
AionLabs: Aion 3.5 costs $3.00 per 1M input tokens and $6.00 per 1M output tokens; Mistral: Mistral Medium 3.1 (batch) costs $0.20 input and $1.00 output. Output tokens are billed separately, so long answers shift the gap.
AionLabs: Aion 3.5: 262K tokens, about 393 pages, against 131K (about 197 pages) for Mistral: Mistral Medium 3.1 (batch).
Tool calling — AionLabs: Aion 3.5: yes, Mistral: Mistral Medium 3.1 (batch): yes. JSON-schema structured output — AionLabs: Aion 3.5: yes, Mistral: Mistral Medium 3.1 (batch): yes.
Only Mistral: Mistral Medium 3.1 (batch) accepts image input; AionLabs: Aion 3.5 is text-only for input.
No free variant is listed for either; both are pay-per-token.
AionLabs: Aion 3.5 can write up to 33K tokens (about 24,600 words) per response; Mistral: Mistral Medium 3.1 (batch) up to 105K (about 78,600 words).
AionLabs: Aion 3.5 was listed on 2026-09-23; Mistral: Mistral Medium 3.1 (batch) on 2025-08-13.
AionLabs: Aion 3.5: price unchanged since we started tracking it on 2026-09-24. Mistral: Mistral Medium 3.1 (batch): input price cut 50% ($0.40 → $0.20/1M), output price cut 50% ($2.00 → $1.00/1M) on 2026-09-10.
Aion 3.5 is a multi-model roleplaying and storytelling system from AionLabs, built on the GLM family of models. It uses a collaborative generation process in which multiple specialized models each...
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Full Mistral: Mistral Medium 3.1 (batch) specs →