Skip to main content
AI Choice Engine

Model comparison

Step 5 Preview vs Xiaomi MiMo-V2.5-Pro

StepFun against Xiaomi, compared on context, price, and verified benchmark results.

Catalog record checked September 26, 2026Individual provider fields may changeEvidence confidence: High — see receipts below

StepFun

Step 5 Preview

Frontier

vs

Xiaomi

Xiaomi MiMo-V2.5-Pro

Frontier · Open weights

AI model capability comparison
SpecificationStep 5 PreviewXiaomi MiMo-V2.5-Pro
ProviderStepFunXiaomi
TierFrontierFrontier
Context window1M1M
Max outputNot verifiedUnverifiedNot verifiedUnverified
Input / 1M tokens$1Winner: $0.435
Output / 1M tokens$2.70Winner: $0.87
WeightsClosedOpen
Parameters600B total / 27B active MoE (StepFun)1.02T total / 42B active (MoE)
Reasoning levelsNot verifiedUnverifiedlow, high, max
Modalitiestext, imagetext, image
LicenseNot disclosedUnverifiedMIT
API model idstep-5-previewmimo-v2-5-pro
ReleasedSeptember 18, 2026April 22, 2026
Artificial Analysis Intelligence Index (2026-09-26)Winner: 43.726

Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

Where each score comes from, and how far it can be compared across models.

  • 2026-09-26
    Artificial Analysis

    Composite index blending reasoning, knowledge, and coding evals into one 0–100 score.

    Comparable with caveatOnly same-version scores are comparable. v4.3.2 was rebaselined (the top score fell from 66 on v4.1.1 to ~58), so v4.1.1 figures must not be compared with v4.3.2 figures — check measuredAt.

Pricing tiers

Step 5 Preview: $1.00/$2.70 per MTok on the StepFun platform (cache-hit input $0.05); StepFun lists it under Multimodal Reasoning Models and says output tokens include reasoning. No max-output figure is published. StepFun says open weights follow on 2026-10-15. Release date per Artificial Analysis's listing (StepFun's launch page is undated).

Xiaomi MiMo-V2.5-Pro: $0.435/$0.87 per MTok (cache hit $0.0036) after Xiaomi's 2026-05-27 V2.5 price cut — the V2.6 launch post says pricing is unchanged from V2.5. The earlier $1/$3 list and its >256K tier no longer apply. Open weights (MIT). 1.02T/42B active MoE.

FrontierRecord checked September 26, 2026

Step 5 Preview

Step 5 Preview is StepFun's new frontier reasoning model — a 1M-context, vision-input API preview that lands near Kimi K3 and GLM 5.3 on the Artificial Analysis index at a lower price.

Best for

  • Long-context work on a budget
  • Chinese + English
  • Early testing before the open-weight drop

Watch out

Preview: weights are promised for 2026-10-15 but not yet released, and its max output is unpublished and the launch benchmarks are vendor-run.

FrontierOpen weightsRecord checked September 26, 2026

Xiaomi MiMo-V2.5-Pro

MiMo-V2.5-Pro is Xiaomi's open-weight (MIT) 1.02T MoE with native multimodal and a 1M context.

Best for

  • Open-weight frontier
  • Multimodal
  • Long-context

Watch out

Verify weights/pricing on your endpoint.

When the cheaper one wins

Xiaomi MiMo-V2.5-Pro is cheaper on output at $0.87 per million tokens against $2.70 for Step 5 Preview — about 3.1×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.

Run the model picker

Evidence confidence: High

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

  • Pricing verified on both sides — Input and output rates are verified for both models.
  • 3/5 core specs verified on both sides — Not published for at least one side: max output, reasoning levels.
  • 1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
  • Verified within the last 90 days — Newest catalog check was 2 days ago.
  • Both models carry source citations — Each side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

Common questions

Step 5 Preview vs Xiaomi MiMo-V2.5-Pro

Answered from the verified figures on this page rather than general guidance.

Is Step 5 Preview or Xiaomi MiMo-V2.5-Pro cheaper for input?
Xiaomi MiMo-V2.5-Pro is cheaper at $0.435 per million input tokens, against $1 for Step 5 Preview — roughly 2.3× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Step 5 Preview has tiered pricing: $1.00/$2.70 per MTok on the StepFun platform (cache-hit input $0.05); StepFun lists it under Multimodal Reasoning Models and says output tokens include reasoning. No max-output figure is published. StepFun says open weights follow on 2026-10-15. Release date per Artificial Analysis's listing (StepFun's launch page is undated). Xiaomi MiMo-V2.5-Pro has tiered pricing: $0.435/$0.87 per MTok (cache hit $0.0036) after Xiaomi's 2026-05-27 V2.5 price cut — the V2.6 launch post says pricing is unchanged from V2.5. The earlier $1/$3 list and its >256K tier no longer apply. Open weights (MIT). 1.02T/42B active MoE.
Is Step 5 Preview or Xiaomi MiMo-V2.5-Pro cheaper for output?
Xiaomi MiMo-V2.5-Pro is cheaper at $0.87 per million output tokens, against $2.70 for Step 5 Preview — roughly 3.1× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Step 5 Preview has tiered pricing: $1.00/$2.70 per MTok on the StepFun platform (cache-hit input $0.05); StepFun lists it under Multimodal Reasoning Models and says output tokens include reasoning. No max-output figure is published. StepFun says open weights follow on 2026-10-15. Release date per Artificial Analysis's listing (StepFun's launch page is undated). Xiaomi MiMo-V2.5-Pro has tiered pricing: $0.435/$0.87 per MTok (cache hit $0.0036) after Xiaomi's 2026-05-27 V2.5 price cut — the V2.6 launch post says pricing is unchanged from V2.5. The earlier $1/$3 list and its >256K tier no longer apply. Open weights (MIT). 1.02T/42B active MoE.
Which has the larger context window, Step 5 Preview or Xiaomi MiMo-V2.5-Pro?
Both accept about 1M tokens of context, so document length will not decide between them.
Should I use Step 5 Preview or Xiaomi MiMo-V2.5-Pro?
Both sit in the frontier tier, so the choice usually comes down to price and context rather than capability. Step 5 Preview suits long-context work on a budget; Xiaomi MiMo-V2.5-Pro suits open-weight frontier.
Can I self-host Step 5 Preview or Xiaomi MiMo-V2.5-Pro?
Xiaomi MiMo-V2.5-Pro publishes open weights, but self-hosting and third-party provider access depend on the licence, hardware, serving support, and availability. Step 5 Preview is a closed model whose supported access paths are controlled by its provider.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

  • Input price: Xiaomi MiMo-V2.5-Pro costs $0.435 per 1M tokens versus $1 for Step 5 Preview — a 2.3x difference at the headline tier.
  • Measured capability: Step 5 Preview leads Artificial Analysis Intelligence Index 43.7 to 26 (measured 2026-09-26).
  • Deployment: Xiaomi MiMo-V2.5-Pro publishes weights you can self-host; the other is API-only.

Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.