STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Hy4 preview vs Kimi K3.1 Pro

Kimi K3.1 Pro leads Hy4 preview by 12.8 points on StealthMark, 56.7 to 43.9. It leads on 8 of 9 benchmarks, including both games, and Hy4 preview on 1. Kimi K3.1 Pro scores higher on Raccoon, with its largest category advantage in anatomy & construction.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

43.9/100Overall rank 30/53
56.7/100Overall rank 11/53

General Intelligence

41.3/100
53.9/100

Visual Intelligence

48.6/100
62.0/100

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

  • Hy4 preview

BENCHMARK BY BENCHMARK

Where each model leads

  • Hy4 preview
  • Kimi K3.1 Pro
  • Other models
  • Median

DATASHEET

Specs and pricing

Hy4 preview is 4× cheaper per output token. Kimi K3.1 Pro scores higher on StealthMark and runs 1.8× faster in our speed test. Both take about 1M tokens of context.

  • Hy4 preview
  • Kimi K3.1 Pro
  • Other models
  • Median
PricePer 1M output tokens, input below
Hy4 preview: $2.504× cheaper$0.83 inputKimi K3.1 Pro: $10$2 input
Context windowTokens per request, max output below
Hy4 preview: 1MTied64K max outputKimi K3.1 Pro: 1MTied1M max output
Output speedTokens per second, our measurement
Hy4 preview: 64tokens/sKimi K3.1 Pro: 1171.8× fastertokens/s
SizeTotal and active parameters
Hy4 preview: 770B49B activeKimi K3.1 Pro: 2.8T104B activeEstimated
Developer
Tencent Hy TeamMoonshot AI
Released
28 Aug 202623 Oct 2026
Origin
ChinaBoth
Input → output
Text → textText, image, video → text
Architecture
MoE; 78-layer backbone with Gated DSA, 256 routed experts + 1 shared expert, top-8 routed experts active, plus native MTP layerPost-trained version of Kimi K3, a Mixture-of-Experts model

Full datasheets, every price and sourceHy4 preview ↗Kimi K3.1 Pro ↗

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.

Hy4 preview 53.1/100Rank 14/47

Survived 1 of 3
Foresight: complete playing field
Level 311 ptsTurn 16 / 20

Kimi K3.1 Pro 61.1/100Rank 10/47

Survived 1 of 3
Foresight: complete playing field
Level 315 ptsTurn 20 / 20

Points per level

LevelHy4 previewKimi K3.1 Pro
Level 1Second Thoughts
26 ptsSurvived
15 ptsOut of lives
Level 2Pressure Pot
6 ptsOut of lives
12 ptsOut of lives
Level 3Hide or Flight
11 ptsOut of lives
15 ptsSurvived

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.

Hy4 preview 35.6/100Rank 31/48

Cleared 3 of 5
Latch: complete playing field
Level 518.2 ptsTurn 19 / 40

Kimi K3.1 Pro 81.8/100Rank 8/48

Cleared 5 of 5
Latch: complete playing field
Level 519.8 ptsTurn 31 / 40

Points per level

LevelHy4 previewKimi K3.1 Pro
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
6 ptsFinished early
9.8 ptsCleared
Level 3Relay vault
18 ptsCleared
19.2 ptsCleared
Level 4Passing bay
15.8 ptsClearedFinished early · 3 beacons left
18.2 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
18.2 ptsFinished early
19.8 ptsCleared

Newton's Mirror

Same task instructions

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

The judgment

Hy4 preview

The central sphere, compact airborne black bead and broad paint ordering are supported. Contact and transport history remain partly unresolved. The optical system provides only isolated first images and light patches, with little evidence of the extensive ordered reflection structure. Rounded metal and paint gloss are more successful than the reflected contents.

Kimi K3.1 Pro

The settled sphere, separate airborne black paint and crimson-before-cyan interaction are supported, with a modest crimson travel overshoot. A shared downward framing displacement remains after accounting for the square canvas. The principal limitation is the reflection system: sparse sphere copies and generic curved bands omit most of the ordered mirror-room structure. Materials receive a small upward revision because bounded bright images and dark bands visibly establish some polish, while soft shading and bulky paint remain separate weaknesses.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
State at 600 ms18.0/2523.5/25
Camera and placement11.5/1510.5/15
Reflections29.5/12026.0/120
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

Hy4 preview

A cohesive, appealing illustration with a serene face, luminous palette and complete framing. The separated head and torso weaken anatomical coherence, while crowded wing attachments and angular sash folds limit the requested suppleness. Clean execution and decorative detail exceed the clarity of the underlying construction.

Kimi K3.1 Pro

The transformed reflection, attentive pose and constellation anatomy clearly communicate introspection. Purposeful fine details enrich a coherent composition. Tubular limbs, crowded lower-body overlaps, shallow depth and limited cast lighting keep the overall execution within the competent range.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
Task & likeness6.0/108.0/10
Anatomy & construction5.5/105.5/10
Space & placement7.5/106.5/10
Light & reflections7.0/106.5/10
Purposeful detail6.5/107.5/10
Artistry & character5.0/107.0/10
Materials & effects7.0/107.0/10
Visual integrity5.5/107.0/10

Benchmark task

Hy4 preview

A young blue dragon floating among clouds tests curved anatomy, expressive features and the contrast between soft clouds and glossy surfaces.

Kimi K3.1 Pro

An imagined creature encounters its reflection. The scene tests original character design, visual self-interpretation and the relationship between a subject and its reflected image.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Hy4 preview

A recognizable but basic Mona Lisa interpretation with a cohesive earthy palette and atmospheric hills. The rigid neck, generic face and unresolved folded-hand pose limit replication and anatomy. Large silhouettes and layer boundaries are comparatively clear, warranting stronger integrity credit than the sparse detail and simplified construction.

Kimi K3.1 Pro

A coherent, recognizable interpretation with controlled color and readable landscape layers. Replication is limited by the frontal seated construction, elongated facial proportions and oversized, weakly articulated hands. Smooth shading supplies some volume but little of the reference's subtle expression, fabric structure or atmospheric transitions.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
Task & likeness2.5/105.0/10
Anatomy & construction2.5/105.0/10
Space & placement2.5/105.5/10
Light & reflections1.5/106.0/10
Purposeful detail2.5/105.5/10
Artistry & character1.5/106.0/10
Materials & effects2.5/105.0/10
Visual integrity4.0/106.5/10

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

Hy4 preview

A cheerful beach illustration fulfills the visible subject requirements with coherent foreground construction and a harmonious sunset palette. Shallow depth, schematic reflections, ambiguous blue airborne forms and exposed geometry beneath the sunset limit its finish. Small accessories are readable, but materials and surface detail remain simplified.

Kimi K3.1 Pro

A coherent, playful beach illustration with readable animals, an organized composition and an aligned sunset reflection. Connected silhouettes, sand texture and atmospheric effects demonstrate controlled execution. Simplified joints, flattened foreground viewpoints and inconsistent shadows limit anatomical and spatial credibility.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
Task & likeness8.5/108.5/10
Anatomy & construction5.5/105.5/10
Space & placement6.5/105.5/10
Light & reflections5.0/106.5/10
Purposeful detail6.0/106.5/10
Artistry & character5.5/105.5/10
Materials & effects5.0/106.5/10
Visual integrity6.0/107.5/10

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

Hy4 preview

This benchmark has not been assessed yet.

Kimi K3.1 Pro

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

Hy4 preview

A lively cartoon communicates the animal pair traveling across water. Curving waves, rising spray and locally modeled gray forms strengthen motion and volume. Ambiguous seating, simplified joints and unclear control routing limit construction. Competing focal elements, decorative foam and inconsistent illumination leave the finish uneven.

Kimi K3.1 Pro

The additional comparisons support retaining the assessment. Readable steering, shaped animal contours and purposeful details coexist with simplified joints, a frontal passenger whose seated weight is weakly conveyed, and limited physical lighting. The angled craft establishes more depth than the riding pose resolves.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
Task & likeness7.0/107.0/10
Anatomy & construction4.0/105.5/10
Space & placement6.0/106.0/10
Light & reflections6.5/105.5/10
Purposeful detail5.5/107.0/10
Artistry & character4.5/106.0/10
Materials & effects5.5/106.0/10
Visual integrity5.0/107.0/10

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

Hy4 preview

A recognizable, playful pelican cyclist with readable wheels, accessories and landscape layers. Form shading and ground shadows provide competent depth. Angular legs, uncertain pedal engagement and absent steering contact limit the riding construction; crowded overlaps and simple surfaces constrain refinement.

Kimi K3.1 Pro

A characterful coastal illustration with controlled contours and varied feather, accessory and bicycle detail. Layered scenery and subtle shading enrich the presentation. Soft leg articulation, unresolved riding contacts, shallow depth and generalized lighting limit physical precision.

Score breakdown

CategoryHy4 previewKimi K3.1 Pro
Task & likeness7.5/108.5/10
Anatomy & construction4.5/107.5/10
Space & placement6.5/106.5/10
Light & reflections7.0/106.5/10
Purposeful detail6.0/107.5/10
Artistry & character5.0/107.5/10
Materials & effects5.0/106.5/10
Visual integrity7.0/107.5/10

Benchmark task

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