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Claude Sonnet 5.5 vs GPT 6 Luna

Claude Sonnet 5.5 scores 13.4 points higher overall (62.7 vs 49.3). Claude Sonnet 5.5 scores higher on Newton's Mirror, with its largest category advantage in reflections.

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Overall StealthMark

62.7/100
49.3/100

General Intelligence

45.2/100
28.2/100

Visual Intelligence

76.1/100
65.1/100

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 Luna20.8/100

GPT 6 Luna: Newton's Mirror SVG benchmark
Researcher observations

The schematic scene supports the paint contact order and compact paint scale. Its low, undersized main sphere and incorrectly placed wall images depart from the reference geometry. A few shrinking wall images provide limited optical organization, while absent lateral recursion and outer chains, broad sphere ribbons and isolated panel highlights leave most nested room and emitter mapping undeveloped.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Sonnet 5.5GPT 6 Luna
State at 600 ms25.0/2522.0/25
Camera and placement15.0/153.5/15
Reflections23.5/1205.0/120
Materials and scale10.0/107.0/10
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 Luna47.3/100

GPT 6 Luna: Selfie SVG benchmark
Researcher observations

Sixfold symmetry, pale coloring and six outward-facing heads establish the motif. However, every neck floats clear of the knot. Squared outer sections replace the required semicircular lobes, and the large stepped opening lacks a regular hexagonal contour. Repeated scales and soft shading suggest skin, but translucent crossings and doubled edges weaken the living, interwoven construction.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Sonnet 5.5GPT 6 Luna
Prompt & likeness8.0/104.5/10
Anatomy & construction8.0/103.5/10
Space & placement8.0/105.5/10
Light & reflections7.5/105.0/10
Purposeful detail7.5/105.0/10
Artistry & character8.0/105.5/10
Materials & effects7.0/105.0/10
Visual integrity8.5/104.5/10

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 Luna76.8/100

GPT 6 Luna: Beach SVG benchmark
Researcher observations

The warm sky, layered sea and framing palms create an appealing composition. Animals, birds, beach activities and a sun reflection fulfill the brief. People have schematic joints and indistinct hands and feet; the airborne dolphin lacks a splash. Limited shadows and surface modeling weaken depth, while clean silhouettes and thoughtful small details support the illustration.

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 Luna
Prompt & likeness9.0/109.0/10
Anatomy & construction7.0/107.0/10
Space & placement8.5/107.5/10
Light & reflections7.5/106.5/10
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 Luna65.5/100

GPT 6 Luna: Mona Lisa SVG benchmark
Researcher observations

The dark veil, crossed arms, restrained smile and layered landscape clearly evoke Mona Lisa. Clean contours and muted colors create a coherent illustration. Replication is limited by enlarged, outlined eyes, simplified facial volume, broad shoulders and indistinct overlapping hands. Gradients suggest depth, but lack the original's subtle painterly transitions.

Exact prompt

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

Compare category scores
CategoryClaude Sonnet 5.5GPT 6 Luna
Prompt & likeness7.0/107.0/10
Anatomy & construction6.0/106.0/10
Space & placement6.5/107.0/10
Light & reflections6.5/106.0/10
Purposeful detail6.0/106.0/10
Artistry & character6.5/106.5/10
Materials & effects5.5/105.5/10
Visual integrity6.5/108.0/10

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 Luna72.5/100

GPT 6 Luna: Raccoon SVG benchmark
Researcher observations

Expressive faces, warm sunset colors and clean silhouettes create an appealing illustration. The raccoon sits on the dog's back, but the dog's grip and steering linkage remain unclear. The broad hull resembles a speedboat, and flat shading, absent sun reflections and modest water displacement limit depth and motion.

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 Luna
Prompt & likeness8.5/108.0/10
Anatomy & construction7.0/106.5/10
Space & placement7.5/107.5/10
Light & reflections6.5/106.0/10
Purposeful detail8.0/107.0/10
Artistry & character8.0/108.0/10
Materials & effects7.5/106.5/10
Visual integrity8.0/108.0/10

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 Luna71.0/100

GPT 6 Luna: Pelican SVG benchmark
Researcher observations

The pelican’s distinctive bill and the coordinated vintage poster palette make an appealing illustration. Circular wheels, orderly spokes and clean lettering strengthen the design. Riding mechanics are less convincing: neither wing reaches the handlebars, pedal contact is ambiguous, and the drivetrain is incomplete. The wheels sit against water without a clear supporting surface. Flat lighting limits volume.

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 Luna
Prompt & likeness9.0/108.0/10
Anatomy & construction7.5/106.0/10
Space & placement7.5/106.5/10
Light & reflections6.5/106.5/10
Purposeful detail8.0/107.5/10
Artistry & character7.5/108.0/10
Materials & effects6.5/106.5/10
Visual integrity8.0/108.0/10