GPT-6 Astra 76.1/100Rank 2/47

STEALTHMARK · HEAD TO HEAD
All comparisons ↗GPT-6 Astra leads Kimi K3.1 Pro by 18.0 points on StealthMark, 74.7 to 56.7. It leads on all 9 benchmarks. GPT-6 Astra scores higher on Newton's Mirror, with its largest category advantage in reflections.
See the difference ↘On every task, result quality and reasoning tokens are each compared with all measured models and weighed equally. Each dot is one model.
BENCHMARK BY BENCHMARK
DATASHEET
GPT-6 Astra scores higher on StealthMark. Kimi K3.1 Pro is 5× cheaper per output token and runs 1.8× faster in our speed test. Both take about 1.05M tokens of context.
Full datasheets, every price and sourceGPT-6 Astra ↗Kimi K3.1 Pro ↗
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.


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.


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


GPT-6 Astra
Major placement and the visible contact sequence are convincing. Dense planar light repetition, recognizable spherical panel images and simplified nested sphere motifs provide useful optical structure. Missing outer chains, truncated distant sequences and incorrect bead-like belts still leave the recursive reflections substantially incomplete.
Kimi K3.1 Pro
The settled sphere, separate airborne black paint and crimson-before-cyan interaction are supported, with a modest crimson travel overshoot. A shared downward framing displacement remains after accounting for the square canvas. The principal limitation is the reflection system: sparse sphere copies and generic curved bands omit most of the ordered mirror-room structure. Materials receive a small upward revision because bounded bright images and dark bands visibly establish some polish, while soft shading and bulky paint remain separate weaknesses.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| State at 600 ms | 25.0/25 | 23.5/25 |
| Camera and placement | 15.0/15 | 10.5/15 |
| Reflections | 70.0/120 | 26.0/120 |
| Materials and scale | 10.0/10 | 7.0/10 |
| Floor-damage reward | 0.0/10 | 0.0/10 |
A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.
Visual construction and creative interpretation.


GPT-6 Astra
The sixfold silhouette, pale coloring, outward heads and central hexagon closely match the brief. Fine scales and soft shading support rounded volume. However, several crossings have conspicuous rectangular seams and weak contact shadows, making the weave feel assembled. Small heads have limited anatomical definition, and the repetitive texture conveys less organic life than requested.
Kimi K3.1 Pro
The transformed reflection, attentive pose and constellation anatomy clearly communicate introspection. Purposeful fine details enrich a coherent composition. Tubular limbs, crowded lower-body overlaps, shallow depth and limited cast lighting keep the overall execution within the competent range.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| Task & likeness | 9.0/10 | 8.0/10 |
| Anatomy & construction | 8.0/10 | 5.5/10 |
| Space & placement | 7.5/10 | 6.5/10 |
| Light & reflections | 7.0/10 | 6.5/10 |
| Purposeful detail | 8.0/10 | 7.5/10 |
| Artistry & character | 8.5/10 | 7.0/10 |
| Materials & effects | 8.0/10 | 7.0/10 |
| Visual integrity | 8.5/10 | 7.0/10 |
GPT-6 Astra
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.
Kimi K3.1 Pro
An imagined creature encounters its reflection. The scene tests original character design, visual self-interpretation and the relationship between a subject and its reflected image.
Precise visual recall and portrait reconstruction.


GPT-6 Astra
The crossed hands, restrained smile, dark clothing and hazy landscape clearly recall the Mona Lisa. Replication is limited by the frontal, elongated face, schematic eyes and stiff fingers. Soft shading gives basic volume, but broad garment shapes and angular scenery lack the original’s nuanced depth and painterly transitions. The frame and composition are controlled; surface grain adds texture without resolving the simplified drawing.
Kimi K3.1 Pro
A coherent, recognizable interpretation with controlled color and readable landscape layers. Replication is limited by the frontal seated construction, elongated facial proportions and oversized, weakly articulated hands. Smooth shading supplies some volume but little of the reference's subtle expression, fabric structure or atmospheric transitions.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| Task & likeness | 6.5/10 | 5.0/10 |
| Anatomy & construction | 6.5/10 | 5.0/10 |
| Space & placement | 6.5/10 | 5.5/10 |
| Light & reflections | 6.5/10 | 6.0/10 |
| Purposeful detail | 6.5/10 | 5.5/10 |
| Artistry & character | 7.0/10 | 6.0/10 |
| Materials & effects | 7.0/10 | 5.0/10 |
| Visual integrity | 7.5/10 | 6.5/10 |
An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.
Creativity, perspective and visual beauty.


GPT-6 Astra
A richly composed sunset beach illustration with cohesive peach, mauve and teal colors. Sweeping palm fronds, a scalloped umbrella and curved shorelines frame the sun and its aligned reflection. Distinct animal silhouettes and carefully distributed beach details reward inspection. Simplified human and dog anatomy, slight dolphin splash cues and inconsistent equipment shadows limit physical conviction.
Kimi K3.1 Pro
A coherent, playful beach illustration with readable animals, an organized composition and an aligned sunset reflection. Connected silhouettes, sand texture and atmospheric effects demonstrate controlled execution. Simplified joints, flattened foreground viewpoints and inconsistent shadows limit anatomical and spatial credibility.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| Task & likeness | 9.0/10 | 8.5/10 |
| Anatomy & construction | 7.5/10 | 5.5/10 |
| Space & placement | 8.5/10 | 5.5/10 |
| Light & reflections | 7.5/10 | 6.5/10 |
| Purposeful detail | 8.5/10 | 6.5/10 |
| Artistry & character | 8.5/10 | 5.5/10 |
| Materials & effects | 7.5/10 | 6.5/10 |
| Visual integrity | 7.5/10 | 7.5/10 |
A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.
Physical reasoning, light and visual reconstruction.


GPT-6 Astra
This benchmark has not been assessed yet.
Kimi K3.1 Pro
This benchmark has not been assessed yet.
A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.
Scene composition and interacting subjects.


GPT-6 Astra
Expressive animals, a balanced sunset composition and sweeping wake make an appealing illustration. The raccoon rides the dog's back, and the dog's connected foreleg reaches the controls. The compact steering assembly and layered paws are less clearly constructed. Lighting remains mostly flat, with little shadow or sun reflection. Clean contours and purposeful details support strong illustrative execution.
Kimi K3.1 Pro
The additional comparisons support retaining the assessment. Readable steering, shaped animal contours and purposeful details coexist with simplified joints, a frontal passenger whose seated weight is weakly conveyed, and limited physical lighting. The angled craft establishes more depth than the riding pose resolves.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| Task & likeness | 8.5/10 | 7.0/10 |
| Anatomy & construction | 7.5/10 | 5.5/10 |
| Space & placement | 8.0/10 | 6.0/10 |
| Light & reflections | 6.5/10 | 5.5/10 |
| Purposeful detail | 8.0/10 | 7.0/10 |
| Artistry & character | 7.5/10 | 6.0/10 |
| Materials & effects | 8.0/10 | 6.0/10 |
| Visual integrity | 8.5/10 | 7.0/10 |
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.
Subject construction and spatial relationships.


GPT-6 Astra
The pelican's long bill, flowing scarf and warm coastal palette create a charming, balanced illustration. Wheels, spokes and frame are largely coherent, but neither wing reaches the handlebars, and the rear leg's pedal contact is unclear. Flat lighting and simplified surfaces limit depth despite clean outlines and attractive feather detail.
Kimi K3.1 Pro
A characterful coastal illustration with controlled contours and varied feather, accessory and bicycle detail. Layered scenery and subtle shading enrich the presentation. Soft leg articulation, unresolved riding contacts, shallow depth and generalized lighting limit physical precision.
| Category | GPT-6 Astra | Kimi K3.1 Pro |
|---|---|---|
| Task & likeness | 8.0/10 | 8.5/10 |
| Anatomy & construction | 7.0/10 | 7.5/10 |
| Space & placement | 7.5/10 | 6.5/10 |
| Light & reflections | 7.0/10 | 6.5/10 |
| Purposeful detail | 8.0/10 | 7.5/10 |
| Artistry & character | 8.0/10 | 7.5/10 |
| Materials & effects | 7.5/10 | 6.5/10 |
| Visual integrity | 8.0/10 | 7.5/10 |
A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.