STEALTHMARK · HEAD TO HEAD

All comparisons ↗

DeepSeek-V4.1-Flash-1017 vs Step 5 Preview

DeepSeek-V4.1-Flash-1017 leads Step 5 Preview by 20.2 points on StealthMark, 59.2 to 39.0. It leads on all 9 benchmarks. DeepSeek-V4.1-Flash-1017 scores higher on Ground Truth.

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All results ↗
All results ↗

Overall StealthMark

59.2/100Overall rank 9/53
39.0/100Overall rank 36/53

General Intelligence

56.8/100
37.1/100

Visual Intelligence

63.5/100
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

  • DeepSeek-V4.1-Flash-1017
  • Step 5 Preview
  • Other models
  • Median

DATASHEET

Specs and pricing

Both take about 1M tokens of context.

  • DeepSeek-V4.1-Flash-1017
  • Step 5 Preview
  • Other models
  • Median
PricePer 1M output tokens, input below
DeepSeek-V4.1-Flash-1017: $1.20$0.30 inputStep 5 Preview: No list price
Context windowTokens per request, max output below
DeepSeek-V4.1-Flash-1017: 1MTied384K max outputStep 5 Preview: 1MTied
Output speedTokens per second, our measurement
DeepSeek-V4.1-Flash-1017: 310tokens/sStep 5 Preview: Not measured
SizeTotal and active parameters
DeepSeek-V4.1-Flash-1017: 763B16B activeEstimatedStep 5 Preview: 600B27B active
Developer
DeepSeek-AIStepFun
Released
17 Oct 2026Not published
Origin
ChinaNot published
Input → output
Text, image → textText, image, video → text
Architecture
Sparse mixture-of-experts with a causal encoder-decoder design and native image understanding.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 sourceDeepSeek-V4.1-Flash-1017 ↗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.

DeepSeek-V4.1-Flash-1017 52.9/100Rank 15/49

Survived 1 of 3
Foresight: complete playing field
Level 310 ptsTurn 15 / 20

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

LevelDeepSeek-V4.1-Flash-1017Step 5 Preview
Level 1Second Thoughts
26 ptsSurvived
22 ptsSurvived
Level 2Pressure Pot
7 ptsOut of lives
Pending
Level 3Hide or Flight
10 ptsOut of lives
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.

DeepSeek-V4.1-Flash-1017 73.9/100Rank 14/50

Cleared 5 of 5
Latch: complete playing field
Level 520 ptsTurn 30 / 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

LevelDeepSeek-V4.1-Flash-1017Step 5 Preview
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.8 ptsCleared
9 ptsCleared
Level 3Relay vault
19.2 ptsCleared
18.6 ptsCleared
Level 4Passing bay
16.4 ptsClearedFinished early · 3 beacons left
15.6 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
20 ptsCleared
15 ptsFinished early

Newton's Mirror

Same task instructions

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

The judgment

DeepSeek-V4.1-Flash-1017

Principal sphere and airborne-black placements are supported, and diminishing bilateral chains provide limited optical structure. Missing nested imagery, incomplete outer chains, distorted first images and sparse emitter recurrence remain the dominant weaknesses. Oversized paint bodies and unresolved cyan contact impose separate limitations.

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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
State at 600 ms23.0/2520.0/25
Camera and placement13.5/1513.5/15
Reflections34.0/12020.0/120
Materials and scale8.5/107.0/10
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

DeepSeek-V4.1-Flash-1017

An expressive, intricately drawn storybook scene with a complete flowing silhouette and differentiated glossy materials. The supported main lens and continuous shrimp body make the central interaction readable, but reciprocal eye lines, facial magnification and the smaller lens grip remain ambiguous. Bright granular fringes and crowded accessory lines limit the 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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
Task & likeness7.5/106.0/10
Anatomy & construction7.5/104.5/10
Space & placement8.0/105.0/10
Light & reflections7.0/105.5/10
Purposeful detail7.5/105.5/10
Artistry & character8.0/105.0/10
Materials & effects7.5/106.0/10
Visual integrity6.5/105.0/10

Benchmark task

DeepSeek-V4.1-Flash-1017

A whale and a tiny shrimp examine one another through bubble lenses, with an octopus nearby. The scene tests interacting characters, differences in scale and transparent materials.

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

DeepSeek-V4.1-Flash-1017

A coherent graphic interpretation with controlled contours, modeled facial volume and purposeful portrait details. Replication remains limited by the frontal pose, enlarged face, altered expression and ambiguous crossed hands. Landscape layering provides depth, while schematic fabric, smooth surfaces and tonal bands constrain the finish.

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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
Task & likeness5.0/104.0/10
Anatomy & construction5.0/104.0/10
Space & placement6.0/104.0/10
Light & reflections6.0/103.5/10
Purposeful detail5.5/104.0/10
Artistry & character5.5/104.0/10
Materials & effects5.5/103.0/10
Visual integrity6.0/103.5/10

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

DeepSeek-V4.1-Flash-1017

A coherent, colorful beach illustration with controlled curves, clean layering and varied readable accessories. Castle details and small animal features strengthen its finish. Schematic airborne animals, uncertain board support, shallow architectural depth and decorative reflections limit physical coherence and drawing sophistication.

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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
Task & likeness7.0/104.0/10
Anatomy & construction5.5/103.0/10
Space & placement5.5/103.5/10
Light & reflections6.0/103.5/10
Purposeful detail6.5/103.0/10
Artistry & character5.0/103.0/10
Materials & effects5.5/103.5/10
Visual integrity4.5/104.0/10

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

DeepSeek-V4.1-Flash-1017

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

Different task instructions

Scene composition and interacting subjects.

The judgment

DeepSeek-V4.1-Flash-1017

An appealing cartoon with recognizable riders, expressive faces and a cohesive twilight palette. Clean shapes support the composition, but ambiguous limb overlaps, weak seat contact and loosely resolved steering limit physical coherence. Lighting and water effects are decorative, with modest material differentiation and drawing complexity.

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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
Task & likeness8.0/104.0/10
Anatomy & construction7.0/104.5/10
Space & placement7.0/103.0/10
Light & reflections6.5/103.5/10
Purposeful detail7.0/104.0/10
Artistry & character7.0/103.5/10
Materials & effects6.5/103.0/10
Visual integrity8.0/103.0/10

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

DeepSeek-V4.1-Flash-1017

An expressive, controlled illustration with continuous body construction, substantial bicycle detail and effective landscape depth. Unclear foot-to-pedal and wing-to-handlebar contacts limit physical conviction and local readability. Purposeful detail and composition are stronger than directional lighting and material treatment.

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

CategoryDeepSeek-V4.1-Flash-1017Step 5 Preview
Task & likeness8.5/103.0/10
Anatomy & construction7.0/103.0/10
Space & placement7.5/103.0/10
Light & reflections6.5/103.0/10
Purposeful detail7.5/104.0/10
Artistry & character7.0/103.0/10
Materials & effects7.0/103.0/10
Visual integrity7.5/102.0/10

Benchmark task

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