STEALTHMARK · HEAD TO HEAD

All comparisons ↗

DeepSeek-V4.1-Flash-1017 vs LongCat-2.0

DeepSeek-V4.1-Flash-1017 leads LongCat-2.0 by 33.7 points on StealthMark, 59.2 to 25.5. It leads on 6 of the 7 benchmarks with results for both and LongCat-2.0 on 1. DeepSeek-V4.1-Flash-1017 scores higher on Newton's Mirror, with its largest category advantage in reflections.

See the difference ↘
All results ↗
Model guide ↗

Overall StealthMark

59.2/100Overall rank 9/53
25.5/100Overall rank 45/53

General Intelligence

56.8/100
17.2/100

Visual Intelligence

63.5/100
34.4/100

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

  • LongCat-2.0Multi-step reasoning not measured

Open or local

Open modelMIT
Open modelMIT

BENCHMARK BY BENCHMARK

Where each model leads

  • DeepSeek-V4.1-Flash-1017
  • LongCat-2.0
  • Other models
  • Median

DATASHEET

Specs and pricing

DeepSeek-V4.1-Flash-1017 scores higher on StealthMark and runs 3.6× faster in our speed test. Both take about 1M tokens of context.

  • DeepSeek-V4.1-Flash-1017
  • LongCat-2.0
  • Other models
  • Median
PricePer 1M output tokens, input below
DeepSeek-V4.1-Flash-1017: $1.20Tied$0.30 inputLongCat-2.0: $1.20Tied$0.30 input
Context windowTokens per request, max output below
DeepSeek-V4.1-Flash-1017: 1MTied384K max outputLongCat-2.0: 1MTied
Output speedTokens per second, our measurement
DeepSeek-V4.1-Flash-1017: 3103.6× fastertokens/sLongCat-2.0: 86tokens/s
SizeTotal and active parameters
DeepSeek-V4.1-Flash-1017: 763B16B activeEstimatedLongCat-2.0: Not disclosed
Developer
DeepSeek-AIMeituan
Released
17 Oct 2026Not published
Origin
ChinaBoth
Input → output
Text, image → textText → text
Architecture
Sparse mixture-of-experts with a causal encoder-decoder design and native image understanding.Mixture-of-Experts with LongCat Sparse Attention

Full datasheets, every price and sourceDeepSeek-V4.1-Flash-1017 ↗LongCat-2.0 ↗

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 15/47

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

Points per level

LevelDeepSeek-V4.1-Flash-1017LongCat-2.0
Level 1Second Thoughts
26 ptsSurvived
No run
Level 2Pressure Pot
7 ptsOut of lives
No run
Level 3Hide or Flight
10 ptsOut of lives
No run

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 13/48

Cleared 5 of 5
Latch: complete playing field
Level 520 ptsTurn 30 / 40

Points per level

LevelDeepSeek-V4.1-Flash-1017LongCat-2.0
Level 1Hold the door
5.2 ptsCleared
No run
Level 2Crossfeed
9.8 ptsCleared
No run
Level 3Relay vault
19.2 ptsCleared
No run
Level 4Passing bay
16.4 ptsClearedFinished early · 3 beacons left
No run
Level 5Second thoughts
20 ptsCleared
No run

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.

LongCat-2.0

Cyan lies on the sphere's facing middle rather than showing its recent interaction near the apex. Separate airborne black and elongated crimson support part of the timing sequence. Small side images and an overlapping lower image provide limited reflection ordering, but recursive room structure, nested imagery and emitter mappings are largely absent. The main sphere is smaller and higher in the frame than prescribed, and the surfaces have a soft, matte appearance.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
State at 600 ms23.0/259.5/25
Camera and placement13.5/156.5/15
Reflections34.0/12012.5/120
Materials and scale8.5/105.5/10
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

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.

LongCat-2.0

Amber slit eyes, a pointed beak, cream feathers and gold-trimmed black clothing establish the secretive owl rogue. The head appears frontal rather than lowered, with much of the face exposed. The centered silhouette is effective, but stiff cloak geometry, shallow facial modeling and extremely dark clothing limit depth and finish. Sparse gold markings suggest the requested circuitry only loosely.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
Task & likeness7.5/107.0/10
Anatomy & construction7.5/106.0/10
Space & placement8.0/106.0/10
Light & reflections7.0/105.5/10
Purposeful detail7.5/106.0/10
Artistry & character8.0/106.5/10
Materials & effects7.5/105.5/10
Visual integrity6.5/106.5/10

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.

LongCat-2.0

A cloaked owl with luminous eyes tests expression, fabric folds and the separation of dark forms.

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.

LongCat-2.0

The centered portrait, slight smile, overlapping hands and distant landscape suggest Mona Lisa, but replication is weak. The face has little volume, the shoulders and torso form a narrow wedge, and the hands are fingerless ovals with unresolved wrists. Broad gray background bands provide limited depth. A bright head rim and pale hands contrast with an almost featureless dark figure.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
Task & likeness5.0/100.5/10
Anatomy & construction5.0/100.5/10
Space & placement6.0/100.5/10
Light & reflections6.0/100.5/10
Purposeful detail5.5/100.0/10
Artistry & character5.5/100.5/10
Materials & effects5.5/100.0/10
Visual integrity6.0/100.5/10

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

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.

LongCat-2.0

The sunset, palms, birds and beach animals create a cheerful, readable scene. Clean silhouettes and a vivid sky establish the composition, but construction remains schematic. The right palm appears rooted in open water, shadows have limited connection to the sunset, and the sun’s reflection consists of rigid bands. Small creatures and beach equipment are recognizable but minimally developed.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
Task & likeness7.0/107.5/10
Anatomy & construction5.5/105.5/10
Space & placement5.5/105.5/10
Light & reflections6.0/106.0/10
Purposeful detail6.5/105.0/10
Artistry & character5.0/105.0/10
Materials & effects5.5/103.0/10
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.

LongCat-2.0

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.

LongCat-2.0

The raccoon is recognizable and expressive, with a clear mask and striped tail. The dog's anatomy is poorly resolved, and the flattened craft lacks convincing steering and seating. Feet extend below the hull, weakening the sense of support. An appealing palette, clean shapes and decorative water effects give the illustration some polish.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
Task & likeness8.0/104.0/10
Anatomy & construction7.0/103.0/10
Space & placement7.0/104.5/10
Light & reflections6.5/105.5/10
Purposeful detail7.0/106.0/10
Artistry & character7.0/103.0/10
Materials & effects6.5/105.5/10
Visual integrity8.0/105.0/10

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

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.

LongCat-2.0

A clearly recognizable pelican cycles through a well-composed coastal sunset. Warm colors, flowing scarf, feather contours and bicycle details give the illustration character. The legs connect to the body, but the farther foot's pedal contact and the wing's handlebar grip remain ambiguous. Clean vector shapes provide polish, with limited material texture and directional shading.

Score breakdown

CategoryDeepSeek-V4.1-Flash-1017LongCat-2.0
Task & likeness8.5/108.5/10
Anatomy & construction7.0/107.0/10
Space & placement7.5/108.0/10
Light & reflections6.5/107.5/10
Purposeful detail7.5/108.0/10
Artistry & character7.0/108.5/10
Materials & effects7.0/107.0/10
Visual integrity7.5/108.5/10

Benchmark task

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