> MiMo-V2.6-Pro vs Step 5 Preview: index scores ~178 and ~175 (GPT-4 = 100), API prices, context windows and results on the same independent tests, side by side.

Up to four models

# Compare

Side by side on the same independent tests, with price and context. The link in your address bar shares this exact comparison.

[MiMo-V2.6-Pro](https://themodelindex.org/models/mimo-v2-6-pro/)

[Step 5 Preview](https://themodelindex.org/models/step-5-preview/)

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Next to MiMo-V2.6-Pro

Best closed model, measured

Claude Opus 5.5

Closest rival, another lab

Kimi K3

The version it replaced

MiMo-V2.5-Pro

Where it started

GPT-4

Presets

Best open vs best closed (measured)

Today vs GPT-4 (2023)

Top three labs

US vs China, best of each

[MiMo-V2.6-Pro](https://themodelindex.org/models/mimo-v2-6-pro/)

~178

estimated

Weights

Open

Released

Sep 2026

Price in / out

$0.43 / $0.87

Context

1.05M

Core tests taken

–

[Step 5 Preview](https://themodelindex.org/models/step-5-preview/)

~175

estimated

Weights

Closed

Released

Sep 2026

Price in / out

–

Context

–

Core tests taken

–

MiMo-V2.6-Pro and Step 5 Preview are too close to call (3 points apart, within the uncertainty) (one score is an estimate).

## Test by test · independent results · Epoch AI

MiMo-V2.6-Pro

Step 5 Preview

These models share no independent tests yet.

Only tests that at least two of these models have taken. Bold rows are the core tests shown on every profile; all of these results inform the index score. Task length (METR) is listed below the chart because it is a duration, not a percentage.

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Source: https://themodelindex.org/compare/mimo-v2-6-pro-vs-step-5-preview/ · The Model Index · data as of 2026-10-01