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Comparison · 3 models · Updated Oct 4, 2026

Gemini Robotics-ER 1.6 Preview vs Sakana Namazu vs Seed 2.1 Pro

Too close to call on our weighted score (Sakana Namazu 51, Seed 2.1 Pro 50, Gemini Robotics-ER 1.6 Preview 50). The right pick depends on what you value most.

  1. Google

    Gemini Robotics-ER 1.6 Preview

    Released Apr 14, 2026

    50/100
    • ECI—
    • Price$1.00 / $5.00
    • Context131K
  2. Sakana AI

    Sakana Namazu

    Released Aug 3, 2026

    51/100
    • ECI—
    • Price$0.95 / $4.00
    • Context262K
  3. ByteDance Seed

    Seed 2.1 Pro

    Released Jun 23, 2026

    50/100
    • ECI—
    • Price$0.891 / $4.45
    • Context256K
01 — Verdict

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, Gemini Robotics-ER 1.6 Preview 50/100), so choose by what matters most for your work: Sakana Namazu on price and Sakana Namazu 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 priceSakana NamazuSakana Namazu $1.71 · Seed 2.1 Pro $1.78 · Gemini Robotics-ER 1.6 Preview $2.00 per 1M tokens (3:1 blend)
  • Longest contextSakana NamazuSakana Namazu 262,144 · Seed 2.1 Pro 256,000 · Gemini Robotics-ER 1.6 Preview 131,072 tokens
  • Widest inputsGemini Robotics-ER 1.6 PreviewGemini Robotics-ER 1.6 Preview: Text, Images, Audio, Video · Sakana Namazu: Text, Images, PDFs · Seed 2.1 Pro: Text, Images, Video
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini Robotics-ER 1.6 PreviewSakana NamazuSeed 2.1 Pro
Price50%363938
Inputs & features30%908080
Context window20%243736
Overall100%50/10051/10050/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Gemini Robotics-ER 1.6 Preview vs Sakana Namazu vs Seed 2.1 Pro specifications side by side
SpecificationGemini Robotics-ER 1.6 PreviewGoogleSakana NamazuSakana AISeed 2.1 ProByteDance Seed
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$1.00$0.95$0.891 (best)
Output$5.00$4.00 (best)$4.45
Cached input—$0.15 (best)$0.178
Blended (3:1)$2.00$1.71 (best)$1.78
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersOfficial Sakana AI APIOfficial Volcengine Ark API
Limits
Context window131,072 tokens262,144 tokens (best)256,000 tokens
Max output65,536 tokens65,536 tokens256,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesNo
AudioYesNoNo
VideoYesNoYes
ReasoningYesYesYesminimal · low · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID—sakana-namazudoubao-seed-2-1-pro-260628
API providers15 (best)2
ReleasedApr 14, 2026Aug 3, 2026Jun 23, 2026
Knowledge cutoffJan 2025——
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Gemini Robotics-ER 1.6 Preview$20.00
  • Sakana Namazu$17.50
  • Seed 2.1 Pro$17.81
04 — Questions

Which should you choose?

Which is better: Gemini Robotics-ER 1.6 Preview, Sakana Namazu or Seed 2.1 Pro?

It is close. Our weighted score puts them within a point (Sakana Namazu 51/100, Seed 2.1 Pro 50/100, Gemini Robotics-ER 1.6 Preview 50/100), so choose by what matters most for your work: Sakana Namazu on price and Sakana Namazu 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, Gemini Robotics-ER 1.6 Preview, Sakana Namazu or Seed 2.1 Pro?

Sakana Namazu is cheaper at $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); Gemini Robotics-ER 1.6 Preview costs $1.00 input / $5.00 output per million tokens (median across 1 API provider). At a typical mix of three input tokens to one output token, that is $1.71 per million tokens for Sakana Namazu versus $1.78 for Seed 2.1 Pro (1× as much) and $2.00 for Gemini Robotics-ER 1.6 Preview (1.2× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Gemini Robotics-ER 1.6 Preview has not been scored yet, Sakana Namazu 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 Gemini Robotics-ER 1.6 Preview, Sakana Namazu 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?

Sakana Namazu has the largest context window at 262,144 tokens, against 256,000 for Seed 2.1 Pro and 131,072 for Gemini Robotics-ER 1.6 Preview. Maximum output per response: Gemini Robotics-ER 1.6 Preview up to 65,536, Sakana Namazu up to 65,536, Seed 2.1 Pro up to 256,000 tokens.

Which can read images, PDFs, audio or video?

Gemini Robotics-ER 1.6 Preview accepts text, images, audio and video; Sakana Namazu accepts text, images and PDFs; Seed 2.1 Pro accepts text, images and video. Gemini Robotics-ER 1.6 Preview handles the widest range of inputs.

Are any of these open source?

No. Gemini Robotics-ER 1.6 Preview, Sakana Namazu and Seed 2.1 Pro are proprietary and only available through APIs and apps.

Which is newer?

Sakana Namazu is the newest, released Aug 3, 2026. Seed 2.1 Pro came out Jun 23, 2026; Gemini Robotics-ER 1.6 Preview came out Apr 14, 2026. Knowledge cutoff: Gemini Robotics-ER 1.6 Preview Jan 2025.

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.