Seed 2.1 Pro vs MiMo-V2.5-Pro-UltraSpeed vs Sakana Namazu
Too close to call on our weighted score (Sakana Namazu 51, Seed 2.1 Pro 50, MiMo-V2.5-Pro-UltraSpeed 43). The right pick depends on what you value most.
ByteDance SeedSeed 2.1 Pro
50/100- ECI—
- Price$0.891 / $4.45
- Context256K
XiaomiMiMo-V2.5-Pro-UltraSpeed
43/100- ECI—
- Price$1.30 / $2.61
- Context1.05M
Sakana AI
Sakana Namazu
51/100- ECI—
- Price$0.95 / $4.00
- Context262K
Too close to call
It is close. Our weighted score puts them within a point (Sakana Namazu 51/100, Seed 2.1 Pro 50/100, MiMo-V2.5-Pro-UltraSpeed 43/100), so choose by what matters most for your work: MiMo-V2.5-Pro-UltraSpeed on price and MiMo-V2.5-Pro-UltraSpeed for long inputs. 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 priceMiMo-V2.5-Pro-UltraSpeedMiMo-V2.5-Pro-UltraSpeed $1.63 · Sakana Namazu $1.71 · Seed 2.1 Pro $1.78 per 1M tokens (3:1 blend)
- Longest contextMiMo-V2.5-Pro-UltraSpeedMiMo-V2.5-Pro-UltraSpeed 1,048,576 · Sakana Namazu 262,144 · Seed 2.1 Pro 256,000 tokens
- Widest inputsSeed 2.1 Pro and Sakana NamazuSeed 2.1 Pro: Text, Images, Video · MiMo-V2.5-Pro-UltraSpeed: Text · Sakana Namazu: Text, Images, PDFs
- Self-hostingMiMo-V2.5-Pro-UltraSpeedPublishes downloadable weights
| Measure | Weight | Seed 2.1 Pro | MiMo-V2.5-Pro-UltraSpeed | Sakana Namazu |
|---|---|---|---|---|
| Price | 50% | 38 | 40 | 39 |
| Inputs & features | 30% | 80 | 35 | 80 |
| Context window | 20% | 36 | 61 | 37 |
| Overall | 100% | 50/100 | 43/100 | 51/100 |
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 | Seed 2.1 ProByteDance Seed | MiMo-V2.5-Pro-UltraSpeedXiaomi | Sakana NamazuSakana AI |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $0.891 (best) | $1.30 | $0.95 |
| Output | $4.45 | $2.61 (best) | $4.00 |
| Cached input | $0.178 | $0.011 (best) | $0.15 |
| Blended (3:1) | $1.78 | $1.63 (best) | $1.71 |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official Volcengine Ark API | Official Xiaomi API | Official Sakana AI API |
| Limits | |||
| Context window | 256,000 tokens | 1,048,576 tokens (best) | 262,144 tokens |
| Max output | 256,000 tokens (best) | 131,072 tokens | 65,536 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | No | Yes |
| PDFs | No | No | Yes |
| Audio | No | No | No |
| Video | Yes | No | No |
| Reasoning | Yesminimal · low · medium · high · xhigh · max | Yes | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | No | Yes |
| Availability | |||
| Weights | Proprietary | Open | Proprietary |
| API model ID | doubao-seed-2-1-pro-260628 | mimo-v2.5-pro-ultraspeed | sakana-namazu |
| API providers | 2 | 1 | 5 (best) |
| Released | Jun 23, 2026 | Jun 8, 2026 | Aug 3, 2026 |
| Knowledge cutoff | — | Dec 2024 | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Seed 2.1 Pro$17.81
- MiMo-V2.5-Pro-UltraSpeed$18.27
- Sakana Namazu$17.50
Which should you choose?
Which is better: Seed 2.1 Pro, MiMo-V2.5-Pro-UltraSpeed or Sakana Namazu?
It is close. Our weighted score puts them within a point (Sakana Namazu 51/100, Seed 2.1 Pro 50/100, MiMo-V2.5-Pro-UltraSpeed 43/100), so choose by what matters most for your work: MiMo-V2.5-Pro-UltraSpeed on price and MiMo-V2.5-Pro-UltraSpeed for long inputs. 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, Seed 2.1 Pro, MiMo-V2.5-Pro-UltraSpeed or Sakana Namazu?
MiMo-V2.5-Pro-UltraSpeed is cheaper at $1.30 input / $2.61 output per million tokens (official Xiaomi API price). Sakana Namazu costs $0.95 input / $4.00 output per million tokens (official Sakana AI API price); 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 $1.63 per million tokens for MiMo-V2.5-Pro-UltraSpeed versus $1.71 for Sakana Namazu (1× as much) and $1.78 for Seed 2.1 Pro (1.1× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. Seed 2.1 Pro has not been scored yet, MiMo-V2.5-Pro-UltraSpeed has not been scored yet and Sakana Namazu has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for Seed 2.1 Pro, MiMo-V2.5-Pro-UltraSpeed and Sakana Namazu 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?
MiMo-V2.5-Pro-UltraSpeed has the largest context window at 1,048,576 tokens, against 262,144 for Sakana Namazu and 256,000 for Seed 2.1 Pro. Maximum output per response: Seed 2.1 Pro up to 256,000, MiMo-V2.5-Pro-UltraSpeed up to 131,072, Sakana Namazu up to 65,536 tokens.
Which can read images, PDFs, audio or video?
Seed 2.1 Pro accepts text, images and video; MiMo-V2.5-Pro-UltraSpeed accepts text; Sakana Namazu accepts text, images and PDFs. Seed 2.1 Pro handles the widest range of inputs.
Are any of these open source?
MiMo-V2.5-Pro-UltraSpeed publishes its weights and can be self-hosted; Seed 2.1 Pro and Sakana Namazu is proprietary.
Which is newer?
Sakana Namazu is the newest, released Aug 3, 2026. Seed 2.1 Pro came out Jun 23, 2026; MiMo-V2.5-Pro-UltraSpeed came out Jun 8, 2026. Knowledge cutoff: MiMo-V2.5-Pro-UltraSpeed Dec 2024.
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.
