STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Ling 3.1 Flash vs Step 5 Preview

Ling 3.1 Flash leads Step 5 Preview by 3.2 points on StealthMark, 42.2 to 39.0. Ling 3.1 Flash and Step 5 Preview each lead on 4 of 9 benchmarks, with 1 tied. Step 5 Preview leads both games. Ling 3.1 Flash scores higher on Beach, with its largest category advantage in anatomy & construction.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

42.2/100Overall rank 32/53
39.0/100Overall rank 36/53

General Intelligence

35.5/100
37.1/100

Visual Intelligence

51.2/100
41.9/100

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 modelMIT

BENCHMARK BY BENCHMARK

Where each model leads

  • Ling 3.1 Flash
  • Step 5 Preview
  • Other models
  • Median

DATASHEET

Specs and pricing

Ling 3.1 Flash scores higher on StealthMark. Step 5 Preview takes 4× more context.

  • Ling 3.1 Flash
  • Step 5 Preview
  • Other models
  • Median
PricePer 1M output tokens, input below
Ling 3.1 Flash: $0.90$0.30 inputStep 5 Preview: No list price
Context windowTokens per request, max output below
Ling 3.1 Flash: 256KStep 5 Preview: 1M4× larger
Output speedTokens per second, our measurement
Ling 3.1 Flash: 115tokens/sStep 5 Preview: Not measured
SizeTotal and active parameters
Ling 3.1 Flash: 560B25B activeStep 5 Preview: 600B27B active
Developer
InclusionAIStepFun
Released
29 Sep 2026Not published
Origin
ChinaNot published
Input → output
Text → textText, image, video → text
Architecture
Hybrid-linear MoE; 72 layers (63 KDA, 9 gated MLA); 512 routed experts, 8 selected and 1 shared.Sparse mixture-of-experts; 92 layers (88 MoE), 352 routed experts with 8 selected per token plus a shared expert; grouped-query attention with 512-token sliding windows and full attention every fourth layer; 3 multi-token-prediction layers; vision tower for image and video input

Full datasheets, every price and sourceLing 3.1 Flash ↗Step 5 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.

Ling 3.1 Flash 43.1/100Rank 44/491 of 3 levels

1 of 3 played
Foresight: complete playing field
Level 26 ptsTurn 14 / 18

Step 5 Preview 59.9/100Rank 42/491 of 3 levels

1 of 3 played
Foresight: complete playing field
Level 122 ptsTurn 28 / 28

Points per level

LevelLing 3.1 FlashStep 5 Preview
Level 1Second Thoughts
Pending
22 ptsSurvived
Level 2Pressure Pot
6 ptsOut of lives
Pending
Level 3Hide or Flight
Not played
Pending

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.

Ling 3.1 Flash 45.9/100Rank 38/503 of 5 levels

3 of 5 played
Latch: complete playing field
Level 49.8 ptsTurn 21 / 40

Step 5 Preview 40.7/100Rank 28/50

Cleared 4 of 5
Latch: complete playing field
Level 515 ptsTurn 35 / 40

Points per level

LevelLing 3.1 FlashStep 5 Preview
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.4 ptsCleared
9 ptsCleared
Level 3Relay vault
Pending
18.6 ptsCleared
Level 4Passing bay
9.8 ptsFinished early
15.6 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
Not played
15 ptsFinished early

Newton's Mirror

Same task instructions

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

The judgment

Ling 3.1 Flash

Central placement, separate airborne black paint and the elongated crimson coating earn substantial state and placement credit. Cyan contact remains unresolved. A few isolated sphere images provide limited optical evidence, while the defining repeated mirror structure is missing. Readable opaque metallic volume and restrained paint scale justify increased material credit. Core: 61.5/170; including the floor reward: 61.5/180.

Step 5 Preview

The main sphere, airborne black and small colored features occupy broadly appropriate positions. Most of the defining mirror system is absent, and paint interaction remains only partially supported. The small paint features do not visibly establish a separate volume-scale violation.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
State at 600 ms22.0/2520.0/25
Camera and placement13.5/1513.5/15
Reflections18.0/12020.0/120
Materials and scale7.0/107.0/10
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

Ling 3.1 Flash

An appealing, coherent storybook ant with a clear expression, complete silhouette and readable signal mechanism. Clean curves and warm accents support the composition, while simplified joints, schematic hardware, limited material differentiation and modest light interaction constrain its finish.

Step 5 Preview

A charming diagonal climber and warm palette communicate the central idea. Simple rounded construction, crowded limb counting, uncertain footholds and an unattached upper shelf limit its physical coherence. Growth bands and the yarn trail add specificity, but the requested material distinctions and unravelled bootie remain underdeveloped.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
Task & likeness7.5/106.0/10
Anatomy & construction7.5/104.5/10
Space & placement7.0/105.0/10
Light & reflections7.5/105.5/10
Purposeful detail7.0/105.5/10
Artistry & character7.0/105.0/10
Materials & effects6.5/106.0/10
Visual integrity8.0/105.0/10

Benchmark task

Ling 3.1 Flash

An ant tending signals in a miniature workshop tests insect anatomy, purposeful gestures and the placement of small objects in a lit environment.

Step 5 Preview

Character scenes test expression, anatomy, materials and coherent visual construction.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Ling 3.1 Flash

A basic, uneven Mona Lisa interpretation with a clear facial focal point, articulated eyes and modest tonal volume. Weak likeness, oversized head proportions, unclear shoulders, curled bare arms and indistinct hands limit replication. The compressed composition and rectangular torso weaken an otherwise coherent earthy palette.

Step 5 Preview

A recognizable, coherent simplification with purposeful facial contours and differentiated fingers. These provide more construction and detail than the broad silhouette alone suggests. The oversized face, frontal seated pose, unresolved wrists and sparse landscape still substantially limit likeness, depth and finish.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
Task & likeness2.0/104.0/10
Anatomy & construction1.5/104.0/10
Space & placement4.0/104.0/10
Light & reflections3.5/103.5/10
Purposeful detail3.5/104.0/10
Artistry & character2.0/104.0/10
Materials & effects1.5/103.0/10
Visual integrity2.0/103.5/10

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

Ling 3.1 Flash

A coherent sunset illustration with harmonious color, clean silhouettes and readable beach details. Its calm composition works well, while playful activity is modest. Simplified animal anatomy, shallow shoreline layering, repetitive foliage and a geometric reflection limit drawing sophistication and naturalism.

Step 5 Preview

A recognizable sunset beach with clear warm-cool contrast and playful accessories. Basic animal construction, shallow foreground placement and schematic reflections limit spatial and physical credibility. Sparse descriptive detail and abruptly ended sky bands constrain the finish.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
Task & likeness7.5/104.0/10
Anatomy & construction6.0/103.0/10
Space & placement7.0/103.5/10
Light & reflections7.0/103.5/10
Purposeful detail6.5/103.0/10
Artistry & character6.5/103.0/10
Materials & effects6.5/103.5/10
Visual integrity6.0/104.0/10

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

Ling 3.1 Flash

This benchmark has not been assessed yet.

Step 5 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

Same task instructions

Scene composition and interacting subjects.

The judgment

Ling 3.1 Flash

An appealing sunset cartoon with recognizable animals, expressive faces and coherent landscape layers. The sky and warm water streaks provide its strongest rendering. Ambiguous seated support, stiff forelegs, a shallow hull and an unclear steering connection limit construction. Clean shapes and readable accessories add finish, while restrained spray and flat surfaces limit material and motion effects.

Step 5 Preview

Recognizable animals, a bright palette and identifying accessories support a basic cartoon. Primitive anatomy, partial seated support, unresolved steering and weak hull-water contact limit the central action. Lighting and spray provide atmosphere without establishing convincing physical depth.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
Task & likeness7.5/104.0/10
Anatomy & construction5.5/104.5/10
Space & placement7.0/103.0/10
Light & reflections7.0/103.5/10
Purposeful detail7.0/104.0/10
Artistry & character5.5/103.5/10
Materials & effects5.5/103.0/10
Visual integrity6.0/103.0/10

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

Ling 3.1 Flash

A clean, appealing pelican illustration with a readable bicycle and coherent landscape. Bill shading, feather layers and faint wheel shadows provide modest depth. Uncertain pedal contact, simplified leg construction and limited material rendering keep the result within competent illustration quality.

Step 5 Preview

The pelican and bicycle are recognizable, with a pleasant palette and basic diffuse shading. The riding relationship fails physically: the bird is unsupported, the front wheel is unmounted, and pedalling is unresolved. Simple geometric construction and sparse material treatment further limit the drawing.

Score breakdown

CategoryLing 3.1 FlashStep 5 Preview
Task & likeness7.5/103.0/10
Anatomy & construction5.5/103.0/10
Space & placement7.0/103.0/10
Light & reflections6.5/103.0/10
Purposeful detail6.0/104.0/10
Artistry & character6.5/103.0/10
Materials & effects6.5/103.0/10
Visual integrity6.0/102.0/10

Benchmark task

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