ZMIME
Comparison · 3 models · Updated Oct 4, 2026

MiMo-V2.5-Pro-UltraSpeed vs Gemini 3.1 Flash Lite vs Seed 2.1 Pro

Gemini 3.1 Flash Lite comes out ahead, 73 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

    Google

    Gemini 3.1 Flash Lite

    Released May 7, 2026

    73/100
    • ECI—
    • Price$0.25 / $1.50
    • Context1.05M
  3. ByteDance Seed

    Seed 2.1 Pro

    Released Jun 23, 2026

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

Gemini 3.1 Flash Lite is our pick

Gemini 3.1 Flash Lite is the better all-round choice, scoring 73/100 against Seed 2.1 Pro (50) and MiMo-V2.5-Pro-UltraSpeed (43). It leads on price and 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 priceGemini 3.1 Flash LiteGemini 3.1 Flash Lite $0.563 · MiMo-V2.5-Pro-UltraSpeed $1.63 · Seed 2.1 Pro $1.78 per 1M tokens (3:1 blend)
  • Longest contextMiMo-V2.5-Pro-UltraSpeed and Gemini 3.1 Flash LiteMiMo-V2.5-Pro-UltraSpeed 1,048,576 · Gemini 3.1 Flash Lite 1,048,576 · Seed 2.1 Pro 256,000 tokens
  • Widest inputsGemini 3.1 Flash LiteMiMo-V2.5-Pro-UltraSpeed: Text · Gemini 3.1 Flash Lite: Text, Images, PDFs, Audio, Video · Seed 2.1 Pro: Text, Images, Video
  • Self-hostingMiMo-V2.5-Pro-UltraSpeedPublishes downloadable weights
How the score is built
MeasureWeightMiMo-V2.5-Pro-UltraSpeedGemini 3.1 Flash LiteSeed 2.1 Pro
Price50%406238
Inputs & features30%3510080
Context window20%616136
Overall100%43/10073/10050/100

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 Gemini 3.1 Flash Lite vs Seed 2.1 Pro specifications side by side
SpecificationMiMo-V2.5-Pro-UltraSpeedXiaomiGemini 3.1 Flash LiteGoogleSeed 2.1 ProByteDance Seed
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$1.30$0.25 (best)$0.891
Output$2.61$1.50 (best)$4.45
Cached input$0.011 (best)$0.025$0.178
Blended (3:1)$1.63$0.563 (best)$1.78
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Xiaomi APIOfficial Google APIOfficial Volcengine Ark API
Limits
Context window1,048,576 tokens (best)1,048,576 tokens (best)256,000 tokens
Max output131,072 tokens65,536 tokens256,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesNoYesYes
PDFsNoYesNo
AudioNoYesNo
VideoNoYesYes
ReasoningYesYesminimal · low · medium · highYesminimal · low · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsOpenProprietaryProprietary
API model IDmimo-v2.5-pro-ultraspeedgemini-3.1-flash-litedoubao-seed-2-1-pro-260628
API providers123 (best)2
ReleasedJun 8, 2026May 7, 2026Jun 23, 2026
Knowledge cutoffDec 2024Jan 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.

  • MiMo-V2.5-Pro-UltraSpeed$18.27
  • Gemini 3.1 Flash Lite$5.50
  • Seed 2.1 Pro$17.81
04 — Questions

Which should you choose?

Which is better: MiMo-V2.5-Pro-UltraSpeed, Gemini 3.1 Flash Lite or Seed 2.1 Pro?

Gemini 3.1 Flash Lite is the better all-round choice, scoring 73/100 against Seed 2.1 Pro (50) and MiMo-V2.5-Pro-UltraSpeed (43). It leads on price and 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, Gemini 3.1 Flash Lite or Seed 2.1 Pro?

Gemini 3.1 Flash Lite is cheaper at $0.25 input / $1.50 output per million tokens (official Google API price). 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 $0.563 per million tokens for Gemini 3.1 Flash Lite versus $1.63 for MiMo-V2.5-Pro-UltraSpeed (2.9× as much) and $1.78 for Seed 2.1 Pro (3.2× 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, Gemini 3.1 Flash Lite 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, Gemini 3.1 Flash Lite 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 and Gemini 3.1 Flash Lite have the largest context windows (1,048,576 and 1,048,576 tokens), against 256,000 for Seed 2.1 Pro. Maximum output per response: MiMo-V2.5-Pro-UltraSpeed up to 131,072, Gemini 3.1 Flash Lite up to 65,536, Seed 2.1 Pro up to 256,000 tokens.

Which can read images, PDFs, audio or video?

MiMo-V2.5-Pro-UltraSpeed accepts text; Gemini 3.1 Flash Lite accepts text, images, PDFs, audio and video; Seed 2.1 Pro accepts text, images and video. Gemini 3.1 Flash Lite 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; Gemini 3.1 Flash Lite and 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; Gemini 3.1 Flash Lite came out May 7, 2026. Knowledge cutoff: MiMo-V2.5-Pro-UltraSpeed Dec 2024, Gemini 3.1 Flash Lite 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.