LongCat 2.0 vs Aion 3.5 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.
| Spec | LongCat 2.0 | Aion 3.5 | Winner |
|---|---|---|---|
| Maker | Meituan | AionLabs | – |
| Type | Open-weight | Proprietary | MELongCat 2.0 |
| Context window | 1M tokens | 262K tokens | MELongCat 2.0 |
| Input price | $0.3/M · free self-host | $3/M | MELongCat 2.0 |
| Output price | $1.2/M · free self-host | $6/M | MELongCat 2.0 |
| Vision / multimodal | No | No | – |
| Tool / function calling | Yes | Yes | = Tie |
| Self-hostable | Yes | No (API only) | MELongCat 2.0 |
| License | Open weights | Proprietary | MELongCat 2.0 |
LongCat 2.0 is ~5.0× cheaper than Aion 3.5 on output tokens ($1.2 vs $6 per M tokens).
| Capability | LongCat 2.0 | Aion 3.5 |
|---|---|---|
| Open weights (downloadable) | ✓ | ✗ |
| Self-hostable | ✓ | ✗ |
| Runs fully offline | ✓ | ✗ |
| Vision / multimodal | ✗ | ✗ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✗ |
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
| Criterion | LongCat 2.0 | Aion 3.5 |
|---|---|---|
| Cost-efficiency | 4.5 | 4.0 |
| Context window | 5.0 | 4.0 |
| Openness | 5.0 | 1.5 |
| Self-hosting | 5.0 | 1.0 |
| Multimodality | 3.5 | 3.5 |
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.
LongCat 2.0 is a sparse mixture-of-experts language model from Meituan, with 48B active parameters out of 1.6T total. It is suited for coding, repository-level changes, long-horizon problem solving, and agentic...
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...
LongCat 2.0 is open-weight and competitive on many tasks, but Aion 3.5 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.
Yes. LongCat 2.0 has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. Aion 3.5 is API-only and cannot be self-hosted.
LongCat 2.0 costs $1.2/M output vs $6/M for Aion 3.5 — roughly 5x cheaper via API, and free if you self-host.
Choose LongCat 2.0 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 Aion 3.5 if you want frontier capability through a managed API with zero infrastructure to run.
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