STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Beam 1.0 501B A23B vs Kimi K3.1 Pro

Kimi K3.1 Pro leads Beam 1.0 501B A23B by 24.8 points on StealthMark, 56.7 to 31.9. It leads on all 9 benchmarks. Kimi K3.1 Pro 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
56.7/100Overall rank 11/53

General Intelligence

30.9/100
53.9/100

Visual Intelligence

33.8/100
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

BENCHMARK BY BENCHMARK

Where each model leads

  • Beam 1.0 501B A23B
  • Kimi K3.1 Pro
  • Other models
  • Median

DATASHEET

Specs and pricing

Beam 1.0 501B A23B is 10× cheaper per output token and runs 8.3× faster in our speed test. Kimi K3.1 Pro scores higher on StealthMark. Both take about 1M tokens of context.

  • Beam 1.0 501B A23B
  • Kimi K3.1 Pro
  • Other models
  • Median
PricePer 1M output tokens, input below
Beam 1.0 501B A23B: $110× cheaper$0.25 inputKimi K3.1 Pro: $10$2 input
Context windowTokens per request, max output below
Beam 1.0 501B A23B: 1MTied128K max outputKimi K3.1 Pro: 1MTied1M max output
Output speedTokens per second, our measurement
Beam 1.0 501B A23B: 9728.3× fastertokens/sKimi K3.1 Pro: 117tokens/s
SizeTotal and active parameters
Beam 1.0 501B A23B: 501B23.4B activeKimi K3.1 Pro: 2.8T104B activeEstimated
Developer
Reflection AIMoonshot AI
Released
16 Oct 202623 Oct 2026
Origin
United StatesChina
Input → output
Text → textText, image, video → 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 attentionPost-trained version of Kimi K3, a Mixture-of-Experts model

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

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

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

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

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

Points per level

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

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

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

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

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

Points per level

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

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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
State at 600 ms20.5/2523.5/25
Camera and placement11.5/1510.5/15
Reflections2.0/12026.0/120
Materials and scale3.0/107.0/10
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

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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
Task & likeness4.0/108.0/10
Anatomy & construction3.5/105.5/10
Space & placement5.5/106.5/10
Light & reflections5.5/106.5/10
Purposeful detail4.5/107.5/10
Artistry & character4.0/107.0/10
Materials & effects4.5/107.0/10
Visual integrity7.0/107.0/10

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 K3.1 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

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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
Task & likeness0.0/105.0/10
Anatomy & construction0.0/105.0/10
Space & placement0.0/105.5/10
Light & reflections0.5/106.0/10
Purposeful detail0.0/105.5/10
Artistry & character0.0/106.0/10
Materials & effects0.0/105.0/10
Visual integrity0.0/106.5/10

Benchmark task

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

Beach

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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
Task & likeness7.0/108.5/10
Anatomy & construction5.0/105.5/10
Space & placement6.0/105.5/10
Light & reflections5.0/106.5/10
Purposeful detail5.5/106.5/10
Artistry & character4.0/105.5/10
Materials & effects5.0/106.5/10
Visual integrity5.0/107.5/10

Benchmark task

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

Ground Truth

Different task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Beam 1.0 501B A23B

This benchmark has not been assessed yet.

Kimi K3.1 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

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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
Task & likeness5.0/107.0/10
Anatomy & construction3.5/105.5/10
Space & placement5.5/106.0/10
Light & reflections4.0/105.5/10
Purposeful detail6.5/107.0/10
Artistry & character3.5/106.0/10
Materials & effects5.0/106.0/10
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 K3.1 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

CategoryBeam 1.0 501B A23BKimi K3.1 Pro
Task & likeness5.5/108.5/10
Anatomy & construction4.5/107.5/10
Space & placement5.0/106.5/10
Light & reflections4.0/106.5/10
Purposeful detail4.0/107.5/10
Artistry & character4.0/107.5/10
Materials & effects4.0/106.5/10
Visual integrity5.5/107.5/10

Benchmark task

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