STEALTHMARK · HEAD TO HEAD

All comparisons ↗

MiMo-V2.6-Pro vs Nemotron 3 Ultra

MiMo-V2.6-Pro leads Nemotron 3 Ultra by 31.2 points on StealthMark, 47.9 to 16.7. It leads on all 9 benchmarks. MiMo-V2.6-Pro scores higher on Newton's Mirror, with its largest category advantage in state at 600 ms.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

47.9/100Overall rank 21/53
16.7/100Overall rank 49/53

General Intelligence

44.3/100
12.2/100

Visual Intelligence

54.3/100
26.5/100

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
  • Nemotron 3 Ultra
  • Other models
  • Median

DATASHEET

Specs and pricing

MiMo-V2.6-Pro scores higher on StealthMark and is 2.8× cheaper per output token. Nemotron 3 Ultra runs 21% faster in our speed test. Both take about 1M tokens of context.

  • MiMo-V2.6-Pro
  • Nemotron 3 Ultra
  • Other models
  • Median
PricePer 1M output tokens, input below
MiMo-V2.6-Pro: $0.872.8× cheaper$0.43 inputNemotron 3 Ultra: $2.40$0.60 input
Context windowTokens per request, max output below
MiMo-V2.6-Pro: 1MTied128K max outputNemotron 3 Ultra: 1MTied
Output speedTokens per second, our measurement
MiMo-V2.6-Pro: 116tokens/sNemotron 3 Ultra: 13921% fastertokens/s
SizeTotal and active parameters
MiMo-V2.6-Pro: 1.02T42B activeNemotron 3 Ultra: 550B55B active
Developer
XiaomiNVIDIA
Released
21 Sep 20264 Jun 2026
Origin
ChinaUnited States
Input → output
Text, image, video, audio → textText → text
Architecture
Sparse Mixture-of-Experts; OpenRouter maps the route to the released Pro-RL checkpoint. The UltraSpeed edition is a separate routeLatentMoE: Mamba-2 + MoE + Attention hybrid with Multi-Token Prediction

Full datasheets, every price and sourceMiMo-V2.6-Pro ↗Nemotron 3 Ultra ↗

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 13/47

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

Nemotron 3 Ultra 16.9/100Rank 41/47

Survived 0 of 3
Foresight: complete playing field
Level 38 ptsTurn 17 / 20

Points per level

LevelMiMo-V2.6-ProNemotron 3 Ultra
Level 1Second Thoughts
4 ptsOut of lives
4 ptsOut of lives
Level 2Pressure Pot
9 ptsOut of lives
4 ptsOut of lives
Level 3Hide or Flight
19 ptsSurvived
8 ptsOut of lives

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 22/48

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

Nemotron 3 Ultra 5.0/100Rank 42/484 of 5 levels

4 of 5 played
Latch: complete playing field
Level 413.8 ptsTurn 21 / 40

Points per level

LevelMiMo-V2.6-ProNemotron 3 Ultra
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9 ptsClearedFinished early · 1 beacon left
3.2 ptsFinished early
Level 3Relay vault
17.2 ptsClearedFinished early · 1 beacon left
7.4 ptsFinished early
Level 4Passing bay
16 ptsClearedFinished early · 3 beacons left
13.8 ptsFinished early
Level 5Second thoughts
20.4 ptsCleared
Not played

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.

Nemotron 3 Ultra

The candidate establishes a separate airborne black blob and partial crimson overlap, but leaves the paint interaction history and settled support unresolved. Its main silhouette, black placement and lamp projection depart substantially from the required camera geometry. A few faint reflection hints provide little support for the extensive mirror system, while the compact paint volumes are visibly disproportionate.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
State at 600 ms23.0/252.0/25
Camera and placement12.0/153.5/15
Reflections19.0/1204.5/120
Materials and scale7.5/103.0/10
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.

Nemotron 3 Ultra

An endearing mechanical creature is clearly framed, with expressive amber eyes and readable segmented arms. The shell resembles layered green plates more than a deep coiled spiral. Detached-looking construction, absent working contacts and patchy rendering leave the central assembly action substantially unresolved.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
Task & likeness6.5/104.0/10
Anatomy & construction5.0/104.0/10
Space & placement5.5/105.5/10
Light & reflections6.5/105.0/10
Purposeful detail6.5/104.0/10
Artistry & character5.0/103.0/10
Materials & effects6.5/104.0/10
Visual integrity6.0/104.5/10

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.

Nemotron 3 Ultra

A hovering mechanical nautilus tests spiral construction, connected mechanical forms and contrasting metal and illuminated surfaces.

Mona Lisa

Same 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.

Nemotron 3 Ultra

The centered silhouette provides basic organization, but multicolored mottling and geometric overlays leave the portrait unresolved. No readable face, crossed hands, clothing or landscape establishes Mona Lisa replication. Texture and transparency offer limited visual effects without coherent anatomy, lighting or material distinctions.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
Task & likeness3.5/100.5/10
Anatomy & construction3.5/100.0/10
Space & placement4.0/101.0/10
Light & reflections5.0/100.5/10
Purposeful detail3.0/100.5/10
Artistry & character4.0/101.5/10
Materials & effects4.0/100.0/10
Visual integrity6.0/100.5/10

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.

Nemotron 3 Ultra

A recognizable beach illustration with appealing warm-cool contrast, readable layers and mostly clean shapes. Unresolved seat construction, schematic animals and broad geometric foliage give it an elementary finish. Weakly coordinated reflections and limited material differentiation further constrain depth and atmosphere.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
Task & likeness8.5/106.5/10
Anatomy & construction5.0/103.0/10
Space & placement6.0/105.0/10
Light & reflections6.5/101.5/10
Purposeful detail6.5/104.5/10
Artistry & character5.0/103.0/10
Materials & effects6.0/102.5/10
Visual integrity6.0/106.5/10

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.

Nemotron 3 Ultra

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.

Nemotron 3 Ultra

The masked raccoon, dog and orange craft make the scene recognizable, with an appealing sunset palette. Overlapping bodies obscure the riding relationship, and the dog's connection to the controls remains unresolved. Weak water displacement, inconsistent shading and visible shape artifacts limit the finish. Ambiguous attachments do not establish detached limbs or inverted anatomy.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
Task & likeness7.0/103.5/10
Anatomy & construction5.0/101.5/10
Space & placement5.5/104.5/10
Light & reflections5.5/102.0/10
Purposeful detail6.0/103.5/10
Artistry & character4.0/101.5/10
Materials & effects5.5/103.0/10
Visual integrity4.5/102.0/10

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.

Nemotron 3 Ultra

A recognizable, playful pelican dominates a readable bicycle scene. Its bill and silhouette succeed, but feet below the pedals and confused drivetrain connections weaken the riding action. Local material modeling adds interest; overlapping contours, repetitive detail and inconsistent shadows leave the illustration basic and uneven.

Score breakdown

CategoryMiMo-V2.6-ProNemotron 3 Ultra
Task & likeness6.5/104.0/10
Anatomy & construction5.0/103.5/10
Space & placement6.0/103.5/10
Light & reflections5.5/104.0/10
Purposeful detail6.0/105.5/10
Artistry & character6.0/104.0/10
Materials & effects5.5/106.0/10
Visual integrity6.0/103.0/10

Benchmark task

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