STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Beam 1.0 501B A23B vs Hy4 preview

Hy4 preview leads Beam 1.0 501B A23B by 12.0 points on StealthMark, 43.9 to 31.9. It leads on 8 of 9 benchmarks, including Foresight, and Beam 1.0 501B A23B on 1, including Latch. Hy4 preview 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
43.9/100Overall rank 30/53

General Intelligence

30.9/100
41.3/100

Visual Intelligence

33.8/100
48.6/100

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

Open or local

Open modelApache 2.0
Open modelApache-2.0

BENCHMARK BY BENCHMARK

Where each model leads

  • Beam 1.0 501B A23B
  • Hy4 preview
  • Other models
  • Median

DATASHEET

Specs and pricing

Beam 1.0 501B A23B is 2.5× cheaper per output token and runs 15× faster in our speed test. Hy4 preview scores higher on StealthMark. Both take about 1M tokens of context.

  • Beam 1.0 501B A23B
  • Hy4 preview
  • Other models
  • Median
PricePer 1M output tokens, input below
Beam 1.0 501B A23B: $12.5× cheaper$0.25 inputHy4 preview: $2.50$0.83 input
Context windowTokens per request, max output below
Beam 1.0 501B A23B: 1MTied128K max outputHy4 preview: 1MTied64K max output
Output speedTokens per second, our measurement
Beam 1.0 501B A23B: 97215× fastertokens/sHy4 preview: 64tokens/s
SizeTotal and active parameters
Beam 1.0 501B A23B: 501B23.4B activeHy4 preview: 770B49B active
Developer
Reflection AITencent Hy Team
Released
16 Oct 202628 Aug 2026
Origin
United StatesChina
Input → output
Text → textBoth
Architecture
Sparse mixture-of-experts transformer; 52 layers (3 dense, 49 MoE), 256 experts with 8 selected per token; gated GQA and sliding-window attentionMoE; 78-layer backbone with Gated DSA, 256 routed experts + 1 shared expert, top-8 routed experts active, plus native MTP layer

Full datasheets, every price and sourceBeam 1.0 501B A23B ↗Hy4 preview ↗

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

Hy4 preview 53.1/100Rank 14/47

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

Points per level

LevelBeam 1.0 501B A23BHy4 preview
Level 1Second Thoughts
18 ptsOut of lives
26 ptsSurvived
Level 2Pressure Pot
9 ptsOut of lives
6 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

Hy4 preview 35.6/100Rank 31/48

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

Points per level

LevelBeam 1.0 501B A23BHy4 preview
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.6 ptsCleared
6 ptsFinished early
Level 3Relay vault
11.2 ptsFinished early
18 ptsCleared
Level 4Passing bay
3.6 ptsFinished early
15.8 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
5 ptsFinished early
18.2 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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
State at 600 ms20.5/2518.0/25
Camera and placement11.5/1511.5/15
Reflections2.0/12029.5/120
Materials and scale3.0/107.5/10
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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
Task & likeness4.0/106.0/10
Anatomy & construction3.5/105.5/10
Space & placement5.5/107.5/10
Light & reflections5.5/107.0/10
Purposeful detail4.5/106.5/10
Artistry & character4.0/105.0/10
Materials & effects4.5/107.0/10
Visual integrity7.0/105.5/10

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.

Hy4 preview

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

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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
Task & likeness0.0/102.5/10
Anatomy & construction0.0/102.5/10
Space & placement0.0/102.5/10
Light & reflections0.5/101.5/10
Purposeful detail0.0/102.5/10
Artistry & character0.0/101.5/10
Materials & effects0.0/102.5/10
Visual integrity0.0/104.0/10

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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
Task & likeness7.0/108.5/10
Anatomy & construction5.0/105.5/10
Space & placement6.0/106.5/10
Light & reflections5.0/105.0/10
Purposeful detail5.5/106.0/10
Artistry & character4.0/105.5/10
Materials & effects5.0/105.0/10
Visual integrity5.0/106.0/10

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.

Hy4 preview

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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
Task & likeness5.0/107.0/10
Anatomy & construction3.5/104.0/10
Space & placement5.5/106.0/10
Light & reflections4.0/106.5/10
Purposeful detail6.5/105.5/10
Artistry & character3.5/104.5/10
Materials & effects5.0/105.5/10
Visual integrity6.5/105.0/10

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

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.

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.

Score breakdown

CategoryBeam 1.0 501B A23BHy4 preview
Task & likeness5.5/107.5/10
Anatomy & construction4.5/104.5/10
Space & placement5.0/106.5/10
Light & reflections4.0/107.0/10
Purposeful detail4.0/106.0/10
Artistry & character4.0/105.0/10
Materials & effects4.0/105.0/10
Visual integrity5.5/107.0/10

Benchmark task

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