LongCat-2.5-Preview vs Ornith 1.0 397B vs Seed 2.1 Pro
Too close to call on our weighted score (Seed 2.1 Pro 62, LongCat-2.5-Preview 60, Ornith 1.0 397B 51). The right pick depends on what you value most.
Meituan (LongCat)LongCat-2.5-Preview
60/100- ECI—
- Price$0.75 / $2.95
- Context1M
DeepReinforce
Ornith 1.0 397B
51/100- ECI—
- Price—
- Context262K
ByteDance SeedSeed 2.1 Pro
62/100- ECI—
- Price$0.891 / $4.45
- Context256K
Too close to call
It is close. Our weighted score puts them within 2 points (Seed 2.1 Pro 62/100, LongCat-2.5-Preview 60/100, Ornith 1.0 397B 51/100), so choose by what matters most for your work: LongCat-2.5-Preview on price and LongCat-2.5-Preview for long inputs. The score weighs inputs & features 60%, context window 40%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
- CapabilityNot enough dataNo independent benchmark covers every model here yet
- Lowest priceLongCat-2.5-PreviewLongCat-2.5-Preview $1.30 · Seed 2.1 Pro $1.78 per 1M tokens (3:1 blend) · Ornith 1.0 397B unpriced
- Longest contextLongCat-2.5-PreviewLongCat-2.5-Preview 1,000,000 · Ornith 1.0 397B 262,144 · Seed 2.1 Pro 256,000 tokens
- Widest inputsSeed 2.1 ProLongCat-2.5-Preview: Text, Images · Ornith 1.0 397B: Text, Images · Seed 2.1 Pro: Text, Images, Video
- Self-hostingOrnith 1.0 397BPublishes downloadable weights (MIT)
| Measure | Weight | LongCat-2.5-Preview | Ornith 1.0 397B | Seed 2.1 Pro |
|---|---|---|---|---|
| Inputs & features | 60% | 60 | 60 | 80 |
| Context window | 40% | 60 | 37 | 36 |
| Overall | 100% | 60/100 | 51/100 | 62/100 |
Left out because at least one model lacks the data: capability and price. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | LongCat-2.5-PreviewMeituan (LongCat) | Ornith 1.0 397BDeepReinforce | Seed 2.1 ProByteDance Seed |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $0.75 (best) | — | $0.891 |
| Output | $2.95 (best) | — | $4.45 |
| Cached input | — | — | $0.178 |
| Blended (3:1) | $1.30 (best) | — | $1.78 |
| Long-context rate | Same rate | — | Same rate |
| Price source | Median of 1 providers | — | Official Volcengine Ark API |
| Limits | |||
| Context window | 1,000,000 tokens (best) | 262,144 tokens | 256,000 tokens |
| Max output | 131,072 tokens | — | 256,000 tokens (best) |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | No | No | No |
| Audio | No | No | No |
| Video | No | No | Yes |
| Reasoning | Yes | Yes | Yesminimal · low · medium · high · xhigh · max |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | No | Yes |
| Availability | |||
| Weights | Proprietary | OpenMIT | Proprietary |
| API model ID | — | — | doubao-seed-2-1-pro-260628 |
| API providers | 2 | — | 2 |
| Released | Sep 25, 2026 | Jun 25, 2026 | Jun 23, 2026 |
| Knowledge cutoff | — | — | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- LongCat-2.5-Preview$13.40
- Ornith 1.0 397B—
- Seed 2.1 Pro$17.81
Which should you choose?
Which is better: LongCat-2.5-Preview, Ornith 1.0 397B or Seed 2.1 Pro?
It is close. Our weighted score puts them within 2 points (Seed 2.1 Pro 62/100, LongCat-2.5-Preview 60/100, Ornith 1.0 397B 51/100), so choose by what matters most for your work: LongCat-2.5-Preview on price and LongCat-2.5-Preview for long inputs. The score weighs inputs & features 60%, context window 40%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, LongCat-2.5-Preview, Ornith 1.0 397B or Seed 2.1 Pro?
LongCat-2.5-Preview is cheaper at $0.75 input / $2.95 output per million tokens (median across 1 API provider). Seed 2.1 Pro costs $0.891 input / $4.45 output per million tokens (official Volcengine Ark API price). At a typical mix of three input tokens to one output token, that is $1.30 per million tokens for LongCat-2.5-Preview versus $1.78 for Seed 2.1 Pro (1.4× as much). Ornith 1.0 397B has no published per-token price.
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. LongCat-2.5-Preview has not been scored yet, Ornith 1.0 397B has not been scored yet and Seed 2.1 Pro has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for LongCat-2.5-Preview, Ornith 1.0 397B and Seed 2.1 Pro yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.
Which has the bigger context window?
LongCat-2.5-Preview has the largest context window at 1,000,000 tokens, against 262,144 for Ornith 1.0 397B and 256,000 for Seed 2.1 Pro. Maximum output per response: LongCat-2.5-Preview up to 131,072, Seed 2.1 Pro up to 256,000 tokens.
Which can read images, PDFs, audio or video?
LongCat-2.5-Preview accepts text and images; Ornith 1.0 397B accepts text and images; Seed 2.1 Pro accepts text, images and video. Seed 2.1 Pro handles the widest range of inputs.
Are any of these open source?
Ornith 1.0 397B publishes its weights (MIT) and can be self-hosted; LongCat-2.5-Preview and Seed 2.1 Pro is proprietary.
Which is newer?
LongCat-2.5-Preview is the newest, released Sep 25, 2026. Ornith 1.0 397B came out Jun 25, 2026; Seed 2.1 Pro came out Jun 23, 2026.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
