STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Gemini 3.8 Flash vs GPT-6.1 Terra Low

Gemini 3.8 Flash leads GPT-6.1 Terra Low by 6.6 points on StealthMark, 47.9 to 41.3. It leads on 8 of 9 benchmarks, including both games, and GPT-6.1 Terra Low on 1. GPT-6.1 Terra Low scores higher on Mona Lisa, with its largest category advantage in anatomy & construction.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

47.9/100Overall rank 21/55
41.3/100Overall rank 35/55

General Intelligence

43.9/100
34.3/100

Visual Intelligence

55.2/100
53.1/100

BENCHMARK BY BENCHMARK

Where each model leads

  • Gemini 3.8 Flash
  • GPT-6.1 Terra Low
  • Other models
  • Median

DATASHEET

Specs and pricing

  • Gemini 3.8 Flash
  • GPT-6.1 Terra Low
  • Other models
  • Median
PricePer 1M output tokens, input below
Gemini 3.8 Flash: $3.75$0.75 inputGPT-6.1 Terra Low: No list price
Context windowTokens per request, max output below
Gemini 3.8 Flash: 1M64K max outputGPT-6.1 Terra Low: Not published
Output speedTokens per second, our measurement
Gemini 3.8 Flash: 170tokens/sGPT-6.1 Terra Low: Not measured
Developer
GoogleNot published
Released
2 Sep 2026Not published
Origin
United StatesNot published
Input → output
Text, image, video, audio, PDF → textNot published

Full datasheets, every price and sourceGemini 3.8 Flash ↗

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.

Gemini 3.8 Flash 45.4/100Rank 22/51

Survived 1 of 3
Foresight: complete playing field
Level 311 ptsTurn 17 / 20

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

LevelGemini 3.8 FlashGPT-6.1 Terra Low
Level 1Second Thoughts
4 ptsOut of lives
4 ptsOut of lives
Level 2Pressure Pot
10 ptsSurvived
8 ptsOut of lives
Level 3Hide or Flight
11 ptsOut of lives
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.

Gemini 3.8 Flash 72.9/100Rank 16/52

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

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

LevelGemini 3.8 FlashGPT-6.1 Terra Low
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.8 ptsCleared
9.2 ptsCleared
Level 3Relay vault
18.8 ptsCleared
18.8 ptsCleared
Level 4Passing bay
17.8 ptsClearedFinished early · 1 beacon left
10.2 ptsFinished early
Level 5Second thoughts
20.6 ptsCleared
20.6 ptsCleared

Newton's Mirror

Same task instructions

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

The judgment

Gemini 3.8 Flash

Crimson is carried well down the camera-facing surface, supporting its earlier interaction. The depiction remains highly simplified, with imperfect material rendering. Isolated wall and floor images and a few highlights provide scant reflective evidence; displaced first reflections, missing receding chains and absent nested sphere and emitter imagery leave the room's optical structure largely unsupported.

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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
State at 600 ms22.5/2522.0/25
Camera and placement11.0/154.0/15
Reflections4.5/12010.0/120
Materials and scale7.0/106.0/10
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

Gemini 3.8 Flash

The dominant four-point silhouette, luminous color progression, raised brows and enormous grin closely fulfill the brief. Attached, secondary limbs support the exuberant expression. Clean facial drawing and glossy eyes give strong character, while shallow depth, minimally articulated extremities and visible steps in the outer glow limit refinement.

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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
Task & likeness8.0/104.0/10
Anatomy & construction6.0/103.5/10
Space & placement6.5/104.5/10
Light & reflections7.0/105.5/10
Purposeful detail5.0/105.5/10
Artistry & character3.5/105.0/10
Materials & effects5.0/105.5/10
Visual integrity6.5/104.0/10

Benchmark task

Gemini 3.8 Flash

A luminous star-shaped creature tests expressive features, a clear silhouette and smooth colour transitions.

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

Same task instructions

Precise visual recall and portrait reconstruction.

The judgment

Gemini 3.8 Flash

The dark clothing, overlapping hands and hazy landscape make the Mona Lisa reference recognizable. Replication is limited by the frontal, elongated face, heavy mouth and chin, and poorly resolved hands, wrists and forearm. Soft shading gives some volume, but muddy transitions, blunt landscape shapes and rigid facial modeling weaken the portrait’s expression and painterly character.

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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
Task & likeness3.0/105.0/10
Anatomy & construction2.0/104.5/10
Space & placement3.5/105.0/10
Light & reflections3.0/106.0/10
Purposeful detail5.0/105.0/10
Artistry & character3.0/105.5/10
Materials & effects5.0/105.0/10
Visual integrity1.0/106.0/10

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

Gemini 3.8 Flash

A vivid purple-and-gold sunset anchors an appealing beach composition with dolphins, birds, a turtle and playful accessories. Palm silhouettes frame the bright reflection effectively. Sparse animal anatomy, wirelike palm foliage, conspicuously regular reflection bands and limited surface texture keep the execution below exceptional.

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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
Task & likeness9.0/108.0/10
Anatomy & construction7.0/105.5/10
Space & placement7.0/105.5/10
Light & reflections8.0/106.5/10
Purposeful detail7.0/106.0/10
Artistry & character7.0/105.0/10
Materials & effects7.0/105.5/10
Visual integrity8.0/107.5/10

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

Gemini 3.8 Flash

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

Gemini 3.8 Flash

Expressive animals, a bold diagonal hull and sweeping spray create an appealing action scene. The raccoon's support on the dog's back is unclear, and the dog lacks a readable paw-to-control grip and connected steering assembly. Clean graphic shapes and lively accessories are stronger than the anatomical construction. Sunset illumination and reflections remain largely 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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
Task & likeness7.0/106.5/10
Anatomy & construction6.0/105.0/10
Space & placement7.0/105.5/10
Light & reflections6.5/104.5/10
Purposeful detail7.5/106.0/10
Artistry & character7.5/105.0/10
Materials & effects7.5/105.0/10
Visual integrity7.5/106.0/10

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

Same task instructions

Subject construction and spatial relationships.

The judgment

Gemini 3.8 Flash

The pelican’s enormous bill, lively feathers and orange bicycle create a clear, appealing composition. Basket contents, spokes and facial details reward inspection. Both legs connect to the body, but foot-to-pedal placement and wing-to-handlebar contact are ambiguous. Bicycle mechanics and lighting remain schematic, limiting an otherwise polished illustration.

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

CategoryGemini 3.8 FlashGPT-6.1 Terra Low
Task & likeness9.0/107.0/10
Anatomy & construction7.5/105.5/10
Space & placement7.5/106.0/10
Light & reflections7.0/105.5/10
Purposeful detail8.5/106.5/10
Artistry & character8.0/106.0/10
Materials & effects7.0/106.0/10
Visual integrity8.0/106.0/10

Benchmark task

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