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Comparison · 3 models · Updated Oct 4, 2026

MiMo-V2.5-Pro-UltraSpeed vs Nex-N2-Pro vs Seed 2.1 Pro

Nex-N2-Pro comes out ahead, 53 to 50 and 43 on our weighted score, and it is the cheaper option too.

  1. Xiaomi

    MiMo-V2.5-Pro-UltraSpeed

    Released Jun 8, 2026Beta

    43/100
    • ECI—
    • Price$1.30 / $2.61
    • Context1.05M
  2. Our pick

    Nex AGI

    Nex-N2-Pro

    Released Jun 2, 2026

    53/100
    • ECI—
    • Price$0.50 / $2.50
    • Context262K
  3. ByteDance Seed

    Seed 2.1 Pro

    Released Jun 23, 2026

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

Nex-N2-Pro is our pick

Nex-N2-Pro is the better all-round choice, scoring 53/100 against Seed 2.1 Pro (50) and MiMo-V2.5-Pro-UltraSpeed (43). It leads on price. MiMo-V2.5-Pro-UltraSpeed wins on context window. Seed 2.1 Pro wins 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 priceNex-N2-ProNex-N2-Pro $1.00 · MiMo-V2.5-Pro-UltraSpeed $1.63 · 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 · Nex-N2-Pro 262,144 · Seed 2.1 Pro 256,000 tokens
  • Widest inputsSeed 2.1 ProMiMo-V2.5-Pro-UltraSpeed: Text · Nex-N2-Pro: Text, Images · Seed 2.1 Pro: Text, Images, Video
  • Self-hostingMiMo-V2.5-Pro-UltraSpeed and Nex-N2-ProPublishes downloadable weights
How the score is built
MeasureWeightMiMo-V2.5-Pro-UltraSpeedNex-N2-ProSeed 2.1 Pro
Price50%405038
Inputs & features30%357080
Context window20%613736
Overall100%43/10053/10050/100

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.

MiMo-V2.5-Pro-UltraSpeed vs Nex-N2-Pro vs Seed 2.1 Pro specifications side by side
SpecificationMiMo-V2.5-Pro-UltraSpeedXiaomiNex-N2-ProNex AGISeed 2.1 ProByteDance Seed
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$1.30$0.50 (best)$0.891
Output$2.61$2.50 (best)$4.45
Cached input$0.011 (best)—$0.178
Blended (3:1)$1.63$1.00 (best)$1.78
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Xiaomi APIMedian of 1 providersOfficial Volcengine Ark API
Limits
Context window1,048,576 tokens (best)262,144 tokens256,000 tokens
Max output131,072 tokens262,144 tokens (best)256,000 tokens
Inputs and features
TextYesYesYes
ImagesNoYesYes
PDFsNoNoNo
AudioNoNoNo
VideoNoNoYes
ReasoningYesYesYesminimal · low · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsOpenOpenProprietary
API model IDmimo-v2.5-pro-ultraspeed—doubao-seed-2-1-pro-260628
API providers112 (best)
ReleasedJun 8, 2026Jun 2, 2026Jun 23, 2026
Knowledge cutoffDec 2024——
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.

  • MiMo-V2.5-Pro-UltraSpeed$18.27
  • Nex-N2-Pro$10.00
  • Seed 2.1 Pro$17.81
04 — Questions

Which should you choose?

Which is better: MiMo-V2.5-Pro-UltraSpeed, Nex-N2-Pro or Seed 2.1 Pro?

Nex-N2-Pro is the better all-round choice, scoring 53/100 against Seed 2.1 Pro (50) and MiMo-V2.5-Pro-UltraSpeed (43). It leads on price. MiMo-V2.5-Pro-UltraSpeed wins on context window. Seed 2.1 Pro wins 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, MiMo-V2.5-Pro-UltraSpeed, Nex-N2-Pro or Seed 2.1 Pro?

Nex-N2-Pro is cheaper at $0.50 input / $2.50 output per million tokens (median across 1 API provider). MiMo-V2.5-Pro-UltraSpeed costs $1.30 input / $2.61 output per million tokens (official Xiaomi 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 $1.00 per million tokens for Nex-N2-Pro versus $1.63 for MiMo-V2.5-Pro-UltraSpeed (1.6× as much) and $1.78 for Seed 2.1 Pro (1.8× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. MiMo-V2.5-Pro-UltraSpeed has not been scored yet, Nex-N2-Pro 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 MiMo-V2.5-Pro-UltraSpeed, Nex-N2-Pro 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?

MiMo-V2.5-Pro-UltraSpeed has the largest context window at 1,048,576 tokens, against 262,144 for Nex-N2-Pro and 256,000 for Seed 2.1 Pro. Maximum output per response: MiMo-V2.5-Pro-UltraSpeed up to 131,072, Nex-N2-Pro up to 262,144, Seed 2.1 Pro up to 256,000 tokens.

Which can read images, PDFs, audio or video?

MiMo-V2.5-Pro-UltraSpeed accepts text; Nex-N2-Pro 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?

MiMo-V2.5-Pro-UltraSpeed and Nex-N2-Pro publishes its weights and can be self-hosted; Seed 2.1 Pro is proprietary.

Which is newer?

Seed 2.1 Pro is the newest, released Jun 23, 2026. MiMo-V2.5-Pro-UltraSpeed came out Jun 8, 2026; Nex-N2-Pro came out Jun 2, 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.