LongCat-2.0 vs Seed Evolving vs Hy4 preview
Seed Evolving comes out ahead, 50 to 45 and 45 on our weighted score, though Hy4 preview is 30% cheaper per token.
Meituan (LongCat)LongCat-2.0
45/100- ECI—
- Price$0.75 / $2.95
- Context1M
- Our pick
ByteDance SeedSeed Evolving
50/100- ECI—
- Price$0.891 / $4.45
- Context256K
TencentHy4 preview
45/100- ECI—
- Price$0.834 / $2.50
- Context1.02M
Seed Evolving is our pick
Seed Evolving is the better all-round choice, scoring 50/100 against Hy4 preview (45) and LongCat-2.0 (45). It leads on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. 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 priceHy4 previewHy4 preview $1.25 · LongCat-2.0 $1.30 · Seed Evolving $1.78 per 1M tokens (3:1 blend)
- Longest contextHy4 previewHy4 preview 1,024,000 · LongCat-2.0 1,000,000 · Seed Evolving 256,000 tokens
- Widest inputsSeed EvolvingLongCat-2.0: Text · Seed Evolving: Text, Images, Video · Hy4 preview: Text
- Self-hostingHy4 previewPublishes downloadable weights
| Measure | Weight | LongCat-2.0 | Seed Evolving | Hy4 preview |
|---|---|---|---|---|
| Price | 50% | 44 | 38 | 45 |
| Inputs & features | 30% | 35 | 80 | 35 |
| Context window | 20% | 60 | 36 | 60 |
| Overall | 100% | 45/100 | 50/100 | 45/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | LongCat-2.0Meituan (LongCat) | Seed EvolvingByteDance Seed | Hy4 previewTencent |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $0.75 (best) | $0.891 | $0.834 |
| Output | $2.95 | $4.45 | $2.50 (best) |
| Cached input | $0.015 (best) | $0.178 | $0.042 |
| Blended (3:1) | $1.30 | $1.78 | $1.25 (best) |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official LongCat API | Official Volcengine Ark API | Official Tencent TokenHub API |
| Limits | |||
| Context window | 1,000,000 tokens | 256,000 tokens | 1,024,000 tokens (best) |
| Max output | 131,072 tokens | 256,000 tokens (best) | 64,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | No | Yes | No |
| PDFs | No | No | No |
| Audio | No | No | No |
| Video | No | Yes | No |
| Reasoning | Yes | Yesminimal · low · medium · high · xhigh · max | Yeshigh |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | Yes | No |
| Availability | |||
| Weights | Proprietary | Proprietary | Open |
| API model ID | LongCat-2.0 | doubao-seed-evolving | hy4-preview |
| API providers | 5 | 2 | 13 (best) |
| Released | Jun 30, 2026 | Jun 23, 2026 | Aug 28, 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-2.0$13.40
- Seed Evolving$17.81
- Hy4 preview$13.34
Which should you choose?
Which is better: LongCat-2.0, Seed Evolving or Hy4 preview?
Seed Evolving is the better all-round choice, scoring 50/100 against Hy4 preview (45) and LongCat-2.0 (45). It leads on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, LongCat-2.0, Seed Evolving or Hy4 preview?
Hy4 preview is cheaper at $0.834 input / $2.50 output per million tokens (official Tencent TokenHub API price). LongCat-2.0 costs $0.75 input / $2.95 output per million tokens (official LongCat API price); Seed Evolving 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 $1.25 per million tokens for Hy4 preview versus $1.30 for LongCat-2.0 (1× as much) and $1.78 for Seed Evolving (1.4× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. LongCat-2.0 has not been scored yet, Seed Evolving has not been scored yet and Hy4 preview has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for LongCat-2.0, Seed Evolving and Hy4 preview 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?
Hy4 preview has the largest context window at 1,024,000 tokens, against 1,000,000 for LongCat-2.0 and 256,000 for Seed Evolving. Maximum output per response: LongCat-2.0 up to 131,072, Seed Evolving up to 256,000, Hy4 preview up to 64,000 tokens.
Which can read images, PDFs, audio or video?
LongCat-2.0 accepts text; Seed Evolving accepts text, images and video; Hy4 preview accepts text. Seed Evolving handles the widest range of inputs.
Are any of these open source?
Hy4 preview publishes its weights and can be self-hosted; LongCat-2.0 and Seed Evolving is proprietary.
Which is newer?
Hy4 preview is the newest, released Aug 28, 2026. LongCat-2.0 came out Jun 30, 2026; Seed Evolving 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.
