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Claude Sonnet 5.5 vs GPT 6.1 Sol

GPT 6.1 Sol scores 0.6 points higher overall (63.3 vs 62.7). GPT 6.1 Sol leads General Intelligence; Claude Sonnet 5.5 leads Visual Intelligence. GPT 6.1 Sol scores higher on Newton's Mirror, with its largest category advantage in reflections.

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Overall StealthMark

62.7/100
63.3/100

General Intelligence

45.2/100
47.6/100

Visual Intelligence

76.1/100
75.1/100

Newton's Mirror

Same prompt

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

Claude Sonnet 5.540.8/100

Claude Sonnet 5.5: Newton's Mirror SVG benchmark
Researcher observations

The near-field silhouettes, broad perspective and paint contact order are recognizable. Missing outer chains, truncated repetitions and absent ordered imagery within the main and reflected spheres substantially limit the reflection system. Sparse spherical highlights leave much of the curved room and emitter mapping unsupported, despite some plausible planar light sequences.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

GPT 6.1 Sol43.9/100

GPT 6.1 Sol: Newton's Mirror SVG benchmark
Researcher observations

Recognizable first sphere images and several central planar lights provide limited geometric agreement. Missing outer chains, truncated panel sequences and simplified interiors across the main, side and floor spheres leave most of the recursive reflection structure unsupported.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
State at 600 ms25.0/2525.0/25
Camera and placement15.0/1515.0/15
Reflections23.5/12029.0/120
Materials and scale10.0/1010.0/10
Floor-damage reward0.0/100.0/10

Selfie

Different prompts

Claude Sonnet 5.579.0/100

Claude Sonnet 5.5: Selfie SVG benchmark
Researcher observations

The centered coral squid has a friendly, composed expression and a balanced flower-like silhouette. Eight thick arms and two slender tentacles remain visibly connected, with no inverted parts. The mantle is elongated rather than compact, and the arm spacing is uneven. Soft shading gives volume, but dense stippling weakens the requested smooth matte finish; the broad background halo makes depth less precise.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

GPT 6.1 Sol76.5/100

GPT 6.1 Sol: Selfie SVG benchmark
Researcher observations

Six outward-facing heads and evenly arranged loops make the pale interlocking knot immediately readable. Uniform widths, angular inner bends and fine scales preserve its ornamental geometry. The bodies feel more like textured tubes than living muscle: shading is subdued, crossing contact shadows are weak, and visible curved seams interrupt surface continuity. Small heads have readable eyes and jaws but limited anatomical depth.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
Prompt & likeness8.0/108.5/10
Anatomy & construction8.0/107.5/10
Space & placement8.0/108.0/10
Light & reflections7.5/106.5/10
Purposeful detail7.5/107.0/10
Artistry & character8.0/108.0/10
Materials & effects7.0/106.5/10
Visual integrity8.5/108.0/10

Beach

Same prompt

Claude Sonnet 5.582.3/100

Claude Sonnet 5.5: Beach SVG benchmark
Researcher observations

A richly designed beach illustration combines radiant sunset bands, intricate palm fans and playful silhouettes within a cohesive purple, coral and turquoise palette. Carefully varied accessories reward close inspection, while overlapping foreground forms and shoreline layers organize the abundant activity. Dense palm strokes compete with focal subjects; animal anatomy, relative scales and reflected silhouettes remain simplified.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections Make it a masterpiece, no tools allowed

GPT 6.1 Sol77.0/100

GPT 6.1 Sol: Beach SVG benchmark
Researcher observations

A cohesive sunset palette, sweeping shoreline and framing palm create an appealing beach illustration. Animals, birds, play and a prominent sun reflection fulfill the brief. Connected but schematic figures and simplified dolphin anatomy limit construction; stepped reflections and mostly flat surfaces limit lighting and material depth. Small beach accessories remain readable and edges are clean.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
Prompt & likeness9.0/108.5/10
Anatomy & construction7.0/107.0/10
Space & placement8.5/107.5/10
Light & reflections7.5/107.5/10
Purposeful detail9.0/107.5/10
Artistry & character9.5/108.0/10
Materials & effects7.5/107.0/10
Visual integrity7.5/108.5/10

Mona Lisa

Different prompts

Claude Sonnet 5.563.8/100

Claude Sonnet 5.5: Mona Lisa SVG benchmark
Researcher observations

The crossed hands, dark dress, restrained smile and winding landscape clearly recall the Mona Lisa. Replication is limited by the frontal symmetry, wide eyes, elongated neck and flattened fingers. Soft facial shading provides volume, but heavy darkness and pervasive crackle obscure forms. The composition is coherent; the landscape and fabric remain visibly schematic.

Exact prompt

Replicate mona-lisa as SVG Make it a masterpiece, no tools allowed

GPT 6.1 Sol64.8/100

GPT 6.1 Sol: Mona Lisa SVG benchmark
Researcher observations

The recognizable pose, dark clothing and misty landscape form a coherent portrait. Soft facial shading creates volume, but the broad face, outlined eyes and simplified smile limit likeness. Overlapping hands have flattened fingers and ambiguous separation. Angular landscape shapes and sparse fabric detail keep the execution competent rather than masterful.

Exact prompt

Replicate mona-lisa as SVG Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
Prompt & likeness7.0/107.0/10
Anatomy & construction6.0/105.5/10
Space & placement6.5/107.0/10
Light & reflections6.5/107.0/10
Purposeful detail6.0/105.5/10
Artistry & character6.5/106.5/10
Materials & effects5.5/106.0/10
Visual integrity6.5/107.5/10

Raccoon

Same prompt

Claude Sonnet 5.576.3/100

Claude Sonnet 5.5: Raccoon SVG benchmark
Researcher observations

The raccoon clearly rides on the dog's back while the dog grips the jet ski controls. Expressive faces, vivid colors and a sweeping wake make the scene appealing. Visible limbs connect coherently, but overlapping steering paws and an indistinct control mounting weaken construction. Flat character lighting and simplified water limit depth and material realism.

Exact prompt

Generate an SVG: A raccoon sits on a dog's back while the dog steers a jet ski Make it a masterpiece, no tools allowed

GPT 6.1 Sol78.5/100

GPT 6.1 Sol: Raccoon SVG benchmark
Researcher observations

The masked raccoon rides the dog's back, and the dog's forepaw meets a handlebar connected to the deck. Expressive faces, a striped tail and sweeping wake create an appealing composition. Overlapping bodies compress the seating and rear-leg anatomy; hull depth and sunset illumination remain schematic.

Exact prompt

Generate an SVG: A raccoon sits on a dog's back while the dog steers a jet ski Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
Prompt & likeness8.5/108.5/10
Anatomy & construction7.0/107.5/10
Space & placement7.5/107.5/10
Light & reflections6.5/106.5/10
Purposeful detail8.0/108.0/10
Artistry & character8.0/108.5/10
Materials & effects7.5/107.5/10
Visual integrity8.0/108.5/10

Pelican

Benchmax control

Outside General and Visual Intelligence.

Claude Sonnet 5.576.8/100

Claude Sonnet 5.5: Pelican SVG benchmark
Researcher observations

The pelican is immediately recognizable, with an expressive face, generous bill and appealing cycling pose. Spokes, chain, feathers and scarf provide purposeful detail. The bicycle largely holds together, though overlapping angular legs obscure the far foot’s pedal contact. Clean outlines and balanced composition succeed; flat surfaces and limited directional lighting constrain depth.

Exact prompt

Generate an SVG of a pelican riding a bicycle Make it a masterpiece, no tools allowed

GPT 6.1 Sol79.0/100

GPT 6.1 Sol: Pelican SVG benchmark
Researcher observations

A clearly recognizable pelican rides a well-composed bicycle through a warm coastal scene. The expressive bill, restrained palette and carefully drawn wheels give the illustration character. Leg-to-pedal connections are less convincing, especially the obscured far foot. Lighting provides gentle volume but little directional shadow. The small subtitle is clipped at the lower border.

Exact prompt

Generate an SVG of a pelican riding a bicycle Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Sonnet 5.5GPT 6.1 Sol
Prompt & likeness9.0/109.0/10
Anatomy & construction7.5/107.0/10
Space & placement7.5/108.0/10
Light & reflections6.5/107.0/10
Purposeful detail8.0/108.0/10
Artistry & character7.5/108.5/10
Materials & effects6.5/107.5/10
Visual integrity8.0/108.0/10