STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Beam 1.0 501B A23B vs Kimi K3

Kimi K3 leads Beam 1.0 501B A23B by 18.7 points on StealthMark, 50.6 to 31.9. It leads on all 9 benchmarks. Kimi K3 scores higher on Newton's Mirror, with its largest category advantage in reflections.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

31.9/100Overall rank 42/53
50.6/100Overall rank 15/53

General Intelligence

30.9/100
44.4/100

Visual Intelligence

33.8/100
61.4/100

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

Open or local

Open modelApache 2.0
Open modelKimi K3 License

BENCHMARK BY BENCHMARK

Where each model leads

  • Beam 1.0 501B A23B
  • Kimi K3
  • Other models
  • Median

DATASHEET

Specs and pricing

Beam 1.0 501B A23B is 11× cheaper per output token and runs 8.4× faster in our speed test. Kimi K3 scores higher on StealthMark. Both take about 1M tokens of context.

  • Beam 1.0 501B A23B
  • Kimi K3
  • Other models
  • Median
PricePer 1M output tokens, input below
Beam 1.0 501B A23B: $111× cheaper$0.25 inputKimi K3: $10.80$0.24 input
Context windowTokens per request, max output below
Beam 1.0 501B A23B: 1MTied128K max outputKimi K3: 1MTied1M max output
Output speedTokens per second, our measurement
Beam 1.0 501B A23B: 9728.4× fastertokens/sKimi K3: 115tokens/s
SizeTotal and active parameters
Beam 1.0 501B A23B: 501B23.4B activeKimi K3: 2.8T104B active
Developer
Reflection AIMoonshot AI
Released
16 Oct 202616 Jul 2026
Origin
United StatesChina
Input → output
Text → textText, image → text
Architecture
Sparse mixture-of-experts transformer; 52 layers (3 dense, 49 MoE), 256 experts with 8 selected per token; gated GQA and sliding-window attentionMixture-of-Experts with KDA + Gated MLA attention, 896 experts and native vision encoder

Full datasheets, every price and sourceBeam 1.0 501B A23B ↗Kimi K3 ↗

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.

Beam 1.0 501B A23B 49.4/100Rank 18/47

Survived 1 of 3
Foresight: complete playing field
Level 39 ptsTurn 20 / 20

Kimi K3 52.7/100Rank 16/47

Survived 0 of 3
Foresight: complete playing field
Level 311 ptsTurn 17 / 20

Points per level

LevelBeam 1.0 501B A23BKimi K3
Level 1Second Thoughts
18 ptsOut of lives
17 ptsOut of lives
Level 2Pressure Pot
9 ptsOut of lives
10 ptsOut of lives
Level 3Hide or Flight
9 ptsSurvived
11 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.

Beam 1.0 501B A23B 37.3/100Rank 29/48

Cleared 2 of 5
Latch: complete playing field
Level 55 ptsTurn 30 / 40

Kimi K3 57.7/100Rank 20/48

Cleared 3 of 5
Latch: complete playing field
Level 514.2 ptsTurn 4 / 40

Points per level

LevelBeam 1.0 501B A23BKimi K3
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.6 ptsCleared
9.6 ptsCleared
Level 3Relay vault
11.2 ptsFinished early
18.2 ptsClearedFinished early · 3 beacons left
Level 4Passing bay
3.6 ptsFinished early
14.2 ptsFinished early
Level 5Second thoughts
5 ptsFinished early
14.2 ptsFinished early

Newton's Mirror

Same task instructions

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

The judgment

Beam 1.0 501B A23B

Central object placement is fairly close, but the defining mirrored-room structure is missing. The paint colors suggest the required contact order without establishing their different interaction histories. The faint floor oval does not demonstrate valid reflection geometry, so it earns no reflection credit. Rounded volume and glossy paint provide limited material credit despite weak metallic finishes and oversized paint bodies.

Kimi K3

The room fills the complete portrait frame without visible borders or labels. The main sphere and airborne black are convincingly placed within the portrait frame. Paint ordering is supported, but its contact and transport history remains weakly expressed. Symmetric wall ghosts, inverted floor imagery and panel echoes establish a basic mirror system. Diffuse gradients dominate, with little ordered nested imagery or repeated emitter mapping on either planar or spherical surfaces. The wall images sit too low, and the floor image is unusually large and low.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
State at 600 ms20.5/2518.0/25
Camera and placement11.5/158.0/15
Reflections2.0/12024.0/120
Materials and scale3.0/106.5/10
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

Beam 1.0 501B A23B

An appealing expression and warm palette support a coherent simple cartoon. The central polishing joke is not legible: the cloth is unresolved and the nose sits away from the fan. Pointed radial plates, uncertain limb attachments and weak ground contact limit construction, while restrained surface detail limits material richness.

Kimi K3

The indigo creature and warm reflected counterpart create a balanced, contemplative composition. Equations, constellations and book emblems give the transformation meaning. Clean silhouettes and controlled glow support the scene, but minimally articulated legs, shallow spatial cues and smooth, generalized surfaces limit its anatomical and material richness.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
Task & likeness4.0/109.0/10
Anatomy & construction3.5/107.0/10
Space & placement5.5/108.0/10
Light & reflections5.5/107.5/10
Purposeful detail4.5/108.0/10
Artistry & character4.0/108.5/10
Materials & effects4.5/107.5/10
Visual integrity7.0/108.0/10

Benchmark task

Beam 1.0 501B A23B

A golden pangolin polishes its oversized amber tail while its nose smudges the same scale. The scene tests expressive anatomy, physical contact and contrasting translucent, polished and soft materials.

Kimi K3

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

Beam 1.0 501B A23B

The candidate shows a faint warm oval against an almost entirely black field. Minimal placement and smooth tonal variation are visible, but the portrait, anatomy, crossed hands and landscape remain unreadable. The saved comparisons provide no specific evidence supporting a change to the baseline categories.

Kimi K3

The centered portrait, dark veil, folded hands and misty landscape clearly evoke Mona Lisa. Replication is limited by the elongated neck, simplified facial proportions and oval hands with shallow finger marks. Soft shading gives some volume, but pervasive blur substitutes for controlled painterly transitions and precise detail.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
Task & likeness0.0/104.5/10
Anatomy & construction0.0/103.5/10
Space & placement0.0/104.5/10
Light & reflections0.5/104.5/10
Purposeful detail0.0/104.0/10
Artistry & character0.0/104.5/10
Materials & effects0.0/104.5/10
Visual integrity0.0/105.0/10

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

Beam 1.0 501B A23B

A coherent, cheerful beach illustration fulfills the main subjects with clean shapes and a strong sunset focal point. Its basic geometric construction, ambiguous animal anatomy, shallow depth and schematic lighting limit its accomplishment. Decorative details provide interest without developing intricate forms or convincing physical surfaces.

Kimi K3

A coordinated sunset palette, expressive silhouettes and varied small details create a lively, appealing beach illustration. The central sun and framing palm and umbrella organize the busy scene, with clean contours preserving readability. Bodies and people remain diagrammatic, depth is shallow, and inverted figure reflections cross matte-looking sand without convincing surface lighting. Materials and movement are mostly conveyed through flat shapes.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
Task & likeness7.0/108.5/10
Anatomy & construction5.0/107.0/10
Space & placement6.0/107.0/10
Light & reflections5.0/106.5/10
Purposeful detail5.5/108.5/10
Artistry & character4.0/108.5/10
Materials & effects5.0/106.5/10
Visual integrity5.0/107.0/10

Benchmark task

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

Ground Truth

Different task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Beam 1.0 501B A23B

This benchmark has not been assessed yet.

Kimi K3

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

Beam 1.0 501B A23B

A cheerful, readable illustration with recognizable animals, expressive faces and useful accessories. Simple rounded construction limits complexity, while ambiguous steering attachments and weak hull-to-water contact reduce physical coherence. Lighting and surface effects establish the setting without convincing environmental interaction.

Kimi K3

The raccoon rides on the dog's back, and the dog's paw meets a steering assembly connected to the red hull. Expressive faces, a warm sunset and sweeping spray create an appealing composition. Crowded body overlaps obscure some limb connections, and the raccoon's right ear appears slightly separated. Flat shading and stylized reflections limit volume and depth.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
Task & likeness5.0/108.0/10
Anatomy & construction3.5/106.5/10
Space & placement5.5/107.5/10
Light & reflections4.0/107.0/10
Purposeful detail6.5/107.5/10
Artistry & character3.5/106.0/10
Materials & effects5.0/107.5/10
Visual integrity6.5/107.0/10

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

Different task instructions

Subject construction and spatial relationships.

The judgment

Beam 1.0 501B A23B

A cheerful, clearly readable pelican-and-bicycle illustration with clean contours and balanced composition. Simple geometric construction limits artistic complexity, while ambiguous neck and steering overlaps, merged pedal contacts and an incomplete drivetrain weaken physical coherence.

Kimi K3

The pelican and bicycle are immediately recognizable, with an expressive bill, flowing scarf and cheerful composition. Both legs remain attached, but pedal connections and wing contact with the handlebar are weakly resolved. Wheel alignment and landscape layers are coherent. Clean outlines support the illustration, while flat surfaces and limited lighting keep it short of masterful execution.

Score breakdown

CategoryBeam 1.0 501B A23BKimi K3
Task & likeness5.5/108.0/10
Anatomy & construction4.5/106.5/10
Space & placement5.0/107.5/10
Light & reflections4.0/105.0/10
Purposeful detail4.0/106.5/10
Artistry & character4.0/106.0/10
Materials & effects4.0/106.0/10
Visual integrity5.5/106.5/10

Benchmark task

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