STEALTHMARK · HEAD TO HEAD

All comparisons ↗

MiMo-V2.6-Pro vs Step 5 Preview

MiMo-V2.6-Pro leads Step 5 Preview by 8.9 points on StealthMark, 47.9 to 39.0. It leads on all 9 benchmarks. MiMo-V2.6-Pro scores higher on Beach, with its largest category advantage in prompt & likeness.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

47.9/100Overall rank 21/53
39.0/100Overall rank 36/53

General Intelligence

44.3/100
37.1/100

Visual Intelligence

54.3/100
41.9/100

Reasoning efficiency

On every task, result quality and reasoning tokens are each compared with all measured models and weighed equally. Each dot is one model.

Single-step reasoning Result quality weighed against reasoning tokens on a single problem

Multi-step reasoning Result quality weighed against reasoning tokens across connected steps, as in agentic workflows

Open or local

Open modelMIT

BENCHMARK BY BENCHMARK

Where each model leads

  • MiMo-V2.6-Pro
  • Step 5 Preview
  • Other models
  • Median

DATASHEET

Specs and pricing

Both take about 1M tokens of context.

  • MiMo-V2.6-Pro
  • Step 5 Preview
  • Other models
  • Median
PricePer 1M output tokens, input below
MiMo-V2.6-Pro: $0.87$0.43 inputStep 5 Preview: No list price
Context windowTokens per request, max output below
MiMo-V2.6-Pro: 1MTied128K max outputStep 5 Preview: 1MTied
Output speedTokens per second, our measurement
MiMo-V2.6-Pro: 116tokens/sStep 5 Preview: Not measured
SizeTotal and active parameters
MiMo-V2.6-Pro: 1.02T42B activeStep 5 Preview: 600B27B active
Developer
XiaomiStepFun
Released
21 Sep 2026Not published
Origin
ChinaNot published
Input → output
Text, image, video, audio → textText, image, video → text
Architecture
Sparse Mixture-of-Experts; OpenRouter maps the route to the released Pro-RL checkpoint. The UltraSpeed edition is a separate routeSparse mixture-of-experts; 92 layers (88 MoE), 352 routed experts with 8 selected per token plus a shared expert; grouped-query attention with 512-token sliding windows and full attention every fourth layer; 3 multi-token-prediction layers; vision tower for image and video input

Full datasheets, every price and sourceMiMo-V2.6-Pro ↗Step 5 Preview ↗

Anticipating threats and planning ahead. Collect coins while avoiding ghosts. Ghosts move before the player each turn, and collisions cost a life. 3 levels in sequence, up to 66 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.

MiMo-V2.6-Pro 54.6/100Rank 13/49

Survived 1 of 3
Foresight: complete playing field
Level 319 ptsTurn 20 / 20

Step 5 Preview 59.9/100Rank 42/491 of 3 levels

1 of 3 played
Foresight: complete playing field
Level 122 ptsTurn 28 / 28

Points per level

LevelMiMo-V2.6-ProStep 5 Preview
Level 1Second Thoughts
4 ptsOut of lives
22 ptsSurvived
Level 2Pressure Pot
9 ptsOut of lives
Pending
Level 3Hide or Flight
19 ptsSurvived
Pending

Cooperative planning and learning from experience. Coordinate two robots to push numbered cores onto matching sockets. Pressure plates hold doors open; moving either robot uses one turn. 5 levels in sequence, up to 152 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.

MiMo-V2.6-Pro 52.6/100Rank 24/50

Cleared 5 of 5
Latch: complete playing field
Level 520.4 ptsTurn 28 / 40

Step 5 Preview 40.7/100Rank 28/50

Cleared 4 of 5
Latch: complete playing field
Level 515 ptsTurn 35 / 40

Points per level

LevelMiMo-V2.6-ProStep 5 Preview
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9 ptsClearedFinished early · 1 beacon left
9 ptsCleared
Level 3Relay vault
17.2 ptsClearedFinished early · 1 beacon left
18.6 ptsCleared
Level 4Passing bay
16 ptsClearedFinished early · 3 beacons left
15.6 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
20.4 ptsCleared
15 ptsFinished early

Newton's Mirror

Same task instructions

Physics, perspective and recursive reflections, tested together. Explore the test ↗

The judgment

MiMo-V2.6-Pro

The main framing and visible paint-contact story are well supported. Major optical omissions dominate the result: sparse repetitions, undersized first images, missing outer chains and absent curved nested imagery prevent a coherent mirror-room system. The metallic forms remain convincing in volume but have a soft illustrative finish.

Step 5 Preview

The main sphere, airborne black and small colored features occupy broadly appropriate positions. Most of the defining mirror system is absent, and paint interaction remains only partially supported. The small paint features do not visibly establish a separate volume-scale violation.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
State at 600 ms23.0/2520.0/25
Camera and placement12.0/1513.5/15
Reflections19.0/12020.0/120
Materials and scale7.5/107.0/10
Floor-damage reward0.0/100.0/10

Benchmark task

A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.

Selfie

Different task instructions

Visual construction and creative interpretation.

The judgment

MiMo-V2.6-Pro

An appealing rabbit with balanced framing, expressive eyes and purposeful costume accents. Simple frontal construction limits anatomical and spatial accomplishment. The orange orb provides an effective luminous focal point, but unreadable wrist connections weaken the requested gestures and prevent stronger integrity credit.

Step 5 Preview

A charming diagonal climber and warm palette communicate the central idea. Simple rounded construction, crowded limb counting, uncertain footholds and an unattached upper shelf limit its physical coherence. Growth bands and the yarn trail add specificity, but the requested material distinctions and unravelled bootie remain underdeveloped.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
Task & likeness6.5/106.0/10
Anatomy & construction5.0/104.5/10
Space & placement5.5/105.0/10
Light & reflections6.5/105.5/10
Purposeful detail6.5/105.5/10
Artistry & character5.0/105.0/10
Materials & effects6.5/106.0/10
Visual integrity6.0/105.0/10

Benchmark task

MiMo-V2.6-Pro

A small rabbit in an explorer outfit floats with a luminous orb. The scene tests character anatomy, pose and the placement of geometric forms around it.

Step 5 Preview

Character scenes test expression, anatomy, materials and coherent visual construction.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

MiMo-V2.6-Pro

The portrait is recognizable through its dark silhouette, slight smile and muted landscape, but replication is weak. A frontal, oversized head and symmetric torso replace the reference's turned seated pose; angular, separated hands omit its central gesture. Smooth shading maintains coherence while anatomical detail, depth and material rendering remain basic.

Step 5 Preview

A recognizable, coherent simplification with purposeful facial contours and differentiated fingers. These provide more construction and detail than the broad silhouette alone suggests. The oversized face, frontal seated pose, unresolved wrists and sparse landscape still substantially limit likeness, depth and finish.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
Task & likeness3.5/104.0/10
Anatomy & construction3.5/104.0/10
Space & placement4.0/104.0/10
Light & reflections5.0/103.5/10
Purposeful detail3.0/104.0/10
Artistry & character4.0/104.0/10
Materials & effects4.0/103.0/10
Visual integrity6.0/103.5/10

Benchmark task

An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.

Beach

Same task instructions

Creativity, perspective and visual beauty.

The judgment

MiMo-V2.6-Pro

A readable sunset beach with clear requested subjects, appealing framing and purposeful accessories. Schematic anatomy, flattened foreground objects, repetitive water highlights and sparse directional shadows limit construction and physical depth. The kite's unresolved anchor also constrains integrity.

Step 5 Preview

A recognizable sunset beach with clear warm-cool contrast and playful accessories. Basic animal construction, shallow foreground placement and schematic reflections limit spatial and physical credibility. Sparse descriptive detail and abruptly ended sky bands constrain the finish.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
Task & likeness8.5/104.0/10
Anatomy & construction5.0/103.0/10
Space & placement6.0/103.5/10
Light & reflections6.5/103.5/10
Purposeful detail6.5/103.0/10
Artistry & character5.0/103.0/10
Materials & effects6.0/103.5/10
Visual integrity6.0/104.0/10

Benchmark task

A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.

Ground Truth

Same task instructions

Physical reasoning, light and visual reconstruction.

The judgment

MiMo-V2.6-Pro

This benchmark has not been assessed yet.

Step 5 Preview

This benchmark has not been assessed yet.

Benchmark task

A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.

Raccoon

Same task instructions

Scene composition and interacting subjects.

The judgment

MiMo-V2.6-Pro

A coherent, cheerful cartoon with recognizable animals, readable steering contact and useful small details. The dog's orientation follows the craft more successfully than a wholly frontal pose would. Simple anatomy, weak raccoon grip and compressed seating contacts still limit physical credibility. Gradients and spray provide polish without resolving complex construction.

Step 5 Preview

Recognizable animals, a bright palette and identifying accessories support a basic cartoon. Primitive anatomy, partial seated support, unresolved steering and weak hull-water contact limit the central action. Lighting and spray provide atmosphere without establishing convincing physical depth.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
Task & likeness7.0/104.0/10
Anatomy & construction5.0/104.5/10
Space & placement5.5/103.0/10
Light & reflections5.5/103.5/10
Purposeful detail6.0/104.0/10
Artistry & character4.0/103.5/10
Materials & effects5.5/103.0/10
Visual integrity4.5/103.0/10

Benchmark task

A jet-ski scene pairs a canine driver with a raccoon passenger. It tests the placement and contact of interacting subjects, along with vehicle construction.

Pelican

Same task instructions

Subject construction and spatial relationships.

The judgment

MiMo-V2.6-Pro

The distinctive bill, continuous silhouette and detailed wheels establish a readable pelican cyclist. Shaped feathers and soft shading add character, but jointless legs, crowded pedal contacts, absent steering contact and loosely directional lighting limit the construction. The comparisons support retaining the baseline category scores.

Step 5 Preview

The pelican and bicycle are recognizable, with a pleasant palette and basic diffuse shading. The riding relationship fails physically: the bird is unsupported, the front wheel is unmounted, and pedalling is unresolved. Simple geometric construction and sparse material treatment further limit the drawing.

Score breakdown

CategoryMiMo-V2.6-ProStep 5 Preview
Task & likeness6.5/103.0/10
Anatomy & construction5.0/103.0/10
Space & placement6.0/103.0/10
Light & reflections5.5/103.0/10
Purposeful detail6.0/104.0/10
Artistry & character6.0/103.0/10
Materials & effects5.5/103.0/10
Visual integrity6.0/102.0/10

Benchmark task

A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.