STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Fledge Alpha vs GPT-6.1 Terra Low

GPT-6.1 Terra Low leads Fledge Alpha by 5.5 points on StealthMark, 41.3 to 35.8. Fledge Alpha and GPT-6.1 Terra Low each lead on 3 of the 7 benchmarks with results for both, with 1 tied. GPT-6.1 Terra Low scores higher on Newton's Mirror, with its largest category advantage in state at 600 ms.

See the difference ↘
Model guide ↗
All results ↗

Overall StealthMark

35.8/100Overall rank 41/55
41.3/100Overall rank 35/55

General Intelligence

27.1/100
34.3/100

Visual Intelligence

45.2/100
53.1/100

Open or local

BENCHMARK BY BENCHMARK

Where each model leads

  • Fledge Alpha
  • GPT-6.1 Terra Low
  • Other models
  • Median

DATASHEET

Specs and pricing

  • Fledge Alpha
  • GPT-6.1 Terra Low
  • Other models
  • Median
Output speedTokens per second, our measurement
Fledge Alpha: 63tokens/sGPT-6.1 Terra Low: Not measured

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.

GPT-6.1 Terra Low 36.1/100Rank 26/51

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

Points per level

LevelFledge AlphaGPT-6.1 Terra Low
Level 1Second Thoughts
No run
4 ptsOut of lives
Level 2Pressure Pot
No run
8 ptsOut of lives
Level 3Hide or Flight
No run
9 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.

GPT-6.1 Terra Low 62.4/100Rank 23/52

Cleared 4 of 5
Latch: complete playing field
Level 520.6 ptsTurn 27 / 40

Points per level

LevelFledge AlphaGPT-6.1 Terra Low
Level 1Hold the door
No run
5.2 ptsCleared
Level 2Crossfeed
No run
9.2 ptsCleared
Level 3Relay vault
No run
18.8 ptsCleared
Level 4Passing bay
No run
10.2 ptsFinished early
Level 5Second thoughts
No run
20.6 ptsCleared

Newton's Mirror

Same task instructions

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

The judgment

Fledge Alpha

The candidate communicates a round metallic sphere, three paint colors and a separate airborne black blob. Its hovering support relationship, displaced framing and unresolved paint interaction limit physical credit. Sparse planar light ghosts and a soft sphere highlight provide little evidence for the required wall/floor repetitions and curved nested mirror imagery.

GPT-6.1 Terra Low

Deformed colored paint and a separate airborne black body establish readable interaction history. Cyan has travelled too far, framing differs substantially, and the mirror system supplies only elementary bands and oval copies. Missing recursive geometry, nested spherical imagery and emitter mapping remain the dominant weaknesses.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
State at 600 ms9.0/2522.0/25
Camera and placement5.0/154.0/15
Reflections7.5/12010.0/120
Materials and scale3.5/106.0/10
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

Fledge Alpha

A coherent, appealing mascot with expressive eyes, a cheerful beak and a readable swept-back silhouette. Its larger forward foot and trailing feathers suggest a running stride, but the upright body, stiff legs and minimally articulated feet limit convincing motion. Clean flat shapes suit the brief, while uneven feather junctions and incomplete cream accents reduce polish.

GPT-6.1 Terra Low

Six attached outward-facing heads, delicate scales and soft ivory shading establish an orderly decorative motif. Separate paddle-shaped bodies replace the required interlocking loops and leave no enclosed central hexagon. Surface detail provides interest, but repeated simple forms, schematic faces and limited anatomical modeling constrain the result.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
Task & likeness7.5/104.0/10
Anatomy & construction6.5/103.5/10
Space & placement7.0/104.5/10
Light & reflections5.5/105.5/10
Purposeful detail6.5/105.5/10
Artistry & character4.0/105.0/10
Materials & effects6.0/105.5/10
Visual integrity6.5/104.0/10

Benchmark task

Fledge Alpha

An eager young seabird running toward the viewer tests expressive anatomy, balance and a convincing forward-moving pose.

GPT-6.1 Terra Low

A pale serpent woven into an interlocking knot tests connected anatomy, repeated structure and readable overlaps. Organic surface detail must work with the overall geometry.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Fledge Alpha

A recognizable but basic Mona Lisa reinterpretation with a coherent silhouette and subdued palette. Curtain-like hair obscures much of the face, while elongated facial construction and oversized, minimally articulated hands substantially weaken replication. Soft shading supplies modest volume, but anatomy, landscape depth and purposeful detail remain underdeveloped.

GPT-6.1 Terra Low

A recognizable, coherent portrait with purposeful facial detail, warm local volume and layered scenery. The frontal pose, enlarged face, merged hands and shallow clothing construction substantially limit replication and drawing skill. The visible successes support retaining the current assessment.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
Task & likeness3.0/105.0/10
Anatomy & construction3.0/104.5/10
Space & placement2.5/105.0/10
Light & reflections2.5/106.0/10
Purposeful detail3.0/105.0/10
Artistry & character3.0/105.5/10
Materials & effects2.5/105.0/10
Visual integrity2.5/106.0/10

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

Fledge Alpha

A cheerful, recognizable sunset beach with a cohesive warm palette and clear accessories. Simple construction, uncertain palm support, an ambiguous upper boundary and schematic reflections limit depth and finish. The scene communicates its subject successfully but lacks the developed forms, lighting and detail of exceptional illustration.

GPT-6.1 Terra Low

A coherent sunset scene demonstrates the beach, animals, birds and reflections. Flowing silhouettes, warm color transitions and intact attachments are its strongest properties. Simplified anatomy, the turtle's elevated viewing angle and symbolic surface effects constrain drawing complexity and physical depth.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
Task & likeness7.5/108.0/10
Anatomy & construction4.0/105.5/10
Space & placement5.5/105.5/10
Light & reflections5.0/106.5/10
Purposeful detail3.0/106.0/10
Artistry & character3.0/105.0/10
Materials & effects2.5/105.5/10
Visual integrity4.0/107.5/10

Benchmark task

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

Ground Truth

Same task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Fledge Alpha

This benchmark has not been assessed yet.

GPT-6.1 Terra Low

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

Fledge Alpha

An appealing sunset illustration with recognizable characters and a clear riding action. Color, expression and silhouette are stronger than anatomical construction: overlapping paws obscure support, the dog's steering limb is simplified, and the vehicle controls lack definition. The wake conveys movement, while lighting and water reflections remain decorative.

GPT-6.1 Terra Low

Recognizable animals, a coherent craft and sweeping wake make an appealing cartoon. Basic limb construction, weakly demonstrated raccoon seating and limited shared perspective constrain the scene. Small identifying details work well, while lighting and materials remain broadly graphic.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
Task & likeness8.5/106.5/10
Anatomy & construction5.5/105.0/10
Space & placement7.5/105.5/10
Light & reflections6.5/104.5/10
Purposeful detail7.0/106.0/10
Artistry & character5.5/105.0/10
Materials & effects7.0/105.0/10
Visual integrity4.5/106.0/10

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

Fledge Alpha

A clear, cheerful illustration with a recognizable pelican, coherent bicycle silhouette and tidy composition. Simplified leg articulation, steering contact, mechanical detail and lighting keep it at a competent illustrative level.

GPT-6.1 Terra Low

A coherent coastal illustration with a distinctive pelican, controlled contours and clearly organised bicycle wheels. Visible saddle support and shaped neck and wing contours earn credit beyond basic geometric construction. Rubbery legs, unresolved pedal contacts and absent steering contact limit the riding action. Lighting and materials remain restrained and spatially shallow.

Score breakdown

CategoryFledge AlphaGPT-6.1 Terra Low
Task & likeness8.0/107.0/10
Anatomy & construction6.0/105.5/10
Space & placement6.5/106.0/10
Light & reflections4.5/105.5/10
Purposeful detail5.5/106.5/10
Artistry & character5.0/106.0/10
Materials & effects5.5/106.0/10
Visual integrity6.5/106.0/10

Benchmark task

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