STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Kimi K3.1 Pro vs LongCat-2.0

Kimi K3.1 Pro leads LongCat-2.0 by 31.2 points on StealthMark, 56.7 to 25.5. It leads on 6 of the 7 benchmarks with results for both and LongCat-2.0 on 1. Kimi K3.1 Pro scores higher on Newton's Mirror, with its largest category advantage in state at 600 ms.

See the difference ↘
All results ↗
Model guide ↗

Overall StealthMark

56.7/100Overall rank 11/53
25.5/100Overall rank 45/53

General Intelligence

53.9/100
17.2/100

Visual Intelligence

62.0/100
34.4/100

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

  • LongCat-2.0Multi-step reasoning not measured

Open or local

Open modelMIT

BENCHMARK BY BENCHMARK

Where each model leads

  • Kimi K3.1 Pro
  • LongCat-2.0
  • Other models
  • Median

DATASHEET

Specs and pricing

Kimi K3.1 Pro scores higher on StealthMark and runs 35% faster in our speed test. LongCat-2.0 is 8.3× cheaper per output token. Both take about 1M tokens of context.

  • Kimi K3.1 Pro
  • LongCat-2.0
  • Other models
  • Median
PricePer 1M output tokens, input below
Kimi K3.1 Pro: $10$2 inputLongCat-2.0: $1.208.3× cheaper$0.30 input
Context windowTokens per request, max output below
Kimi K3.1 Pro: 1MTied1M max outputLongCat-2.0: 1MTied
Output speedTokens per second, our measurement
Kimi K3.1 Pro: 11735% fastertokens/sLongCat-2.0: 86tokens/s
SizeTotal and active parameters
Kimi K3.1 Pro: 2.8T104B activeEstimatedLongCat-2.0: Not disclosed
Developer
Moonshot AIMeituan
Released
23 Oct 2026Not published
Origin
ChinaBoth
Input → output
Text, image, video → textText → text
Architecture
Post-trained version of Kimi K3, a Mixture-of-Experts modelMixture-of-Experts with LongCat Sparse Attention

Full datasheets, every price and sourceKimi K3.1 Pro ↗LongCat-2.0 ↗

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.

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

LevelKimi K3.1 ProLongCat-2.0
Level 1Second Thoughts
15 ptsOut of lives
No run
Level 2Pressure Pot
12 ptsOut of lives
No run
Level 3Hide or Flight
15 ptsSurvived
No run

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.

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

LevelKimi K3.1 ProLongCat-2.0
Level 1Hold the door
5.2 ptsCleared
No run
Level 2Crossfeed
9.8 ptsCleared
No run
Level 3Relay vault
19.2 ptsCleared
No run
Level 4Passing bay
18.2 ptsClearedFinished early · 3 beacons left
No run
Level 5Second thoughts
19.8 ptsCleared
No run

Newton's Mirror

Same task instructions

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

The judgment

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.

LongCat-2.0

Cyan lies on the sphere's facing middle rather than showing its recent interaction near the apex. Separate airborne black and elongated crimson support part of the timing sequence. Small side images and an overlapping lower image provide limited reflection ordering, but recursive room structure, nested imagery and emitter mappings are largely absent. The main sphere is smaller and higher in the frame than prescribed, and the surfaces have a soft, matte appearance.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
State at 600 ms23.5/259.5/25
Camera and placement10.5/156.5/15
Reflections26.0/12012.5/120
Materials and scale7.0/105.5/10
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

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.

LongCat-2.0

Amber slit eyes, a pointed beak, cream feathers and gold-trimmed black clothing establish the secretive owl rogue. The head appears frontal rather than lowered, with much of the face exposed. The centered silhouette is effective, but stiff cloak geometry, shallow facial modeling and extremely dark clothing limit depth and finish. Sparse gold markings suggest the requested circuitry only loosely.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
Task & likeness8.0/107.0/10
Anatomy & construction5.5/106.0/10
Space & placement6.5/106.0/10
Light & reflections6.5/105.5/10
Purposeful detail7.5/106.0/10
Artistry & character7.0/106.5/10
Materials & effects7.0/105.5/10
Visual integrity7.0/106.5/10

Benchmark task

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.

LongCat-2.0

A cloaked owl with luminous eyes tests expression, fabric folds and the separation of dark forms.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

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.

LongCat-2.0

The centered portrait, slight smile, overlapping hands and distant landscape suggest Mona Lisa, but replication is weak. The face has little volume, the shoulders and torso form a narrow wedge, and the hands are fingerless ovals with unresolved wrists. Broad gray background bands provide limited depth. A bright head rim and pale hands contrast with an almost featureless dark figure.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
Task & likeness5.0/100.5/10
Anatomy & construction5.0/100.5/10
Space & placement5.5/100.5/10
Light & reflections6.0/100.5/10
Purposeful detail5.5/100.0/10
Artistry & character6.0/100.5/10
Materials & effects5.0/100.0/10
Visual integrity6.5/100.5/10

Benchmark task

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

Beach

Different task instructions

Creativity, perspective and visual beauty.

The judgment

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.

LongCat-2.0

The sunset, palms, birds and beach animals create a cheerful, readable scene. Clean silhouettes and a vivid sky establish the composition, but construction remains schematic. The right palm appears rooted in open water, shadows have limited connection to the sunset, and the sun’s reflection consists of rigid bands. Small creatures and beach equipment are recognizable but minimally developed.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
Task & likeness8.5/107.5/10
Anatomy & construction5.5/105.5/10
Space & placement5.5/105.5/10
Light & reflections6.5/106.0/10
Purposeful detail6.5/105.0/10
Artistry & character5.5/105.0/10
Materials & effects6.5/103.0/10
Visual integrity7.5/104.0/10

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

Kimi K3.1 Pro

This benchmark has not been assessed yet.

LongCat-2.0

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

Different task instructions

Scene composition and interacting subjects.

The judgment

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.

LongCat-2.0

The raccoon is recognizable and expressive, with a clear mask and striped tail. The dog's anatomy is poorly resolved, and the flattened craft lacks convincing steering and seating. Feet extend below the hull, weakening the sense of support. An appealing palette, clean shapes and decorative water effects give the illustration some polish.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
Task & likeness7.0/104.0/10
Anatomy & construction5.5/103.0/10
Space & placement6.0/104.5/10
Light & reflections5.5/105.5/10
Purposeful detail7.0/106.0/10
Artistry & character6.0/103.0/10
Materials & effects6.0/105.5/10
Visual integrity7.0/105.0/10

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

Different task instructions

Subject construction and spatial relationships.

The judgment

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.

LongCat-2.0

A clearly recognizable pelican cycles through a well-composed coastal sunset. Warm colors, flowing scarf, feather contours and bicycle details give the illustration character. The legs connect to the body, but the farther foot's pedal contact and the wing's handlebar grip remain ambiguous. Clean vector shapes provide polish, with limited material texture and directional shading.

Score breakdown

CategoryKimi K3.1 ProLongCat-2.0
Task & likeness8.5/108.5/10
Anatomy & construction7.5/107.0/10
Space & placement6.5/108.0/10
Light & reflections6.5/107.5/10
Purposeful detail7.5/108.0/10
Artistry & character7.5/108.5/10
Materials & effects6.5/107.0/10
Visual integrity7.5/108.5/10

Benchmark task

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