Neither wins outright: AionLabs: Aion 3.5 is the pick when you need to fit long inputs in one request, Moondream: Moondream 3.1 when cost matters at scale.
| Spec | AionLabs: Aion 3.5 | Moondream: Moondream 3.1 |
|---|---|---|
| Provider | Aion Labs | Moondream |
| Input price (per 1M tokens) | $3.00 | $0.30 |
| Output price (per 1M tokens) | $6.00 | $2.50 |
| Blended price (3:1 input/output) | $3.75 | $0.85 |
| Cheaper than … of all models we track | 17% | 43% |
| Context window | 262K tokens (~393 pages) | 32K tokens (~48 pages) |
| Larger context than … of all models | 48% | 5% |
| Max output per response | 33K tokens (~24,600 words) | 4K tokens (~3,100 words) |
| Input types | text | text, image |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2026-09-23 | 2026-10-15 |
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 | Moondream: Moondream 3.1 | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $345 | $72.50 | Moondream: Moondream 3.1 saves $273 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $420 | $61.00 | Moondream: Moondream 3.1 saves $359 |
| 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 | Doesn't fit context | — |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $276 | $39.00 | Moondream: Moondream 3.1 saves $237 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $156 | Doesn't fit context | — |
| Capability | AionLabs: Aion 3.5 | Moondream: Moondream 3.1 | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | — | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | — | return JSON that validates against your schema |
| Reasoning / thinking mode | ✓ Yes | ✓ 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 | — | — | 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) | — | — | 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.
Neither wins outright: AionLabs: Aion 3.5 is the pick when you need to fit long inputs in one request, Moondream: Moondream 3.1 when cost matters at scale. In short: AionLabs: Aion 3.5 when you need to fit long inputs in one request, you need tool / function calling, you need structured output (JSON schema), you generate long outputs in one go; Moondream: Moondream 3.1 when cost matters at scale, you need image input.
Moondream: Moondream 3.1 is cheaper: $0.85 vs $3.75 per 1M tokens at a typical 3:1 input/output mix, 77% less. For 50,000 support conversations a month that is $72.50 against $345.
AionLabs: Aion 3.5 costs $3.00 per 1M input tokens and $6.00 per 1M output tokens; Moondream: Moondream 3.1 costs $0.30 input and $2.50 output. Output tokens are billed separately, so long answers shift the gap.
AionLabs: Aion 3.5: 262K tokens, about 393 pages, against 32K (about 48 pages) for Moondream: Moondream 3.1.
Tool calling — AionLabs: Aion 3.5: yes, Moondream: Moondream 3.1: not advertised. JSON-schema structured output — AionLabs: Aion 3.5: yes, Moondream: Moondream 3.1: not advertised.
Only Moondream: Moondream 3.1 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; Moondream: Moondream 3.1 up to 4K (about 3,100 words).
AionLabs: Aion 3.5 was listed on 2026-09-23; Moondream: Moondream 3.1 on 2026-10-15.
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