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Claude Fable 5.1 vs GPT 6 Luna

Claude Fable 5.1 scores 12.8 points higher overall (62.1 vs 49.3). Claude Fable 5.1 scores higher on Newton's Mirror, with its largest category advantage in reflections.

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Overall StealthMark

62.1/100
49.3/100

General Intelligence

54.3/100
28.2/100

Visual Intelligence

67.7/100
65.1/100

Newton's Mirror

Same prompt

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

Claude Fable 5.151.7/100

Claude Fable 5.1: Newton's Mirror SVG benchmark
Researcher observations

The broad paint sequence, bilateral near-field sphere arrangement, overlaps and diminishing panel repetitions are recognizable; crimson is slightly too low. Small paint scale and basic shading provide material cues, although the steel response remains soft. Inaccurate light projections, missing outer chains and incomplete nested room imagery remain the principal limitations.

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 Fable 5.1GPT 6 Luna
State at 600 ms24.0/2522.0/25
Camera and placement14.0/153.5/15
Reflections48.0/1205.0/120
Materials and scale7.0/107.0/10
Floor-damage reward0.0/100.0/10

Selfie

Different prompts

Claude Fable 5.169.0/100

Claude Fable 5.1: Selfie SVG benchmark
Researcher observations

The coral palette, friendly face, matte shading and cream arch create a coherent emblem. However, the mantle is elongated rather than compact, and the appendages spread mostly sideways and downward instead of forming an evenly spaced, flower-like starburst. Two thin hanging appendages weaken the thick-arm motif. Clean contours and balanced framing support the simple design.

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 Fable 5.1GPT 6 Luna
Prompt & likeness6.5/104.5/10
Anatomy & construction6.5/103.5/10
Space & placement7.5/105.5/10
Light & reflections6.5/105.0/10
Purposeful detail6.0/105.0/10
Artistry & character7.5/105.5/10
Materials & effects6.5/105.0/10
Visual integrity8.0/104.5/10

Beach

Same prompt

Claude Fable 5.175.0/100

Claude Fable 5.1: Beach SVG benchmark
Researcher observations

The colorful sunset, layered shoreline, animals, kite and beach toys fulfill the lively beach brief. Clean silhouettes and a balanced composition give the illustration character. Construction is simplified: the umbrella resembles a segmented fan, dolphins have weak water interaction, and the sun’s reflection forms a rigid widening wedge. Flat surfaces and sparse contact shadows limit depth.

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 Fable 5.1GPT 6 Luna
Prompt & likeness8.5/109.0/10
Anatomy & construction7.0/107.0/10
Space & placement7.0/107.5/10
Light & reflections7.0/106.5/10
Purposeful detail7.5/107.5/10
Artistry & character8.0/108.0/10
Materials & effects6.5/107.0/10
Visual integrity8.0/108.5/10

Mona Lisa

Same prompt

Claude Fable 5.156.5/100

Claude Fable 5.1: Mona Lisa SVG benchmark
Researcher observations

The dark clothing, crossed hands and hazy landscape establish the Mona Lisa composition. Replication is limited by the frontal, elongated face, wide eyes and simplified smile. Rounded, parallel fingers and unclear wrist transitions weaken the hands. Warm facial shading gives some volume, but broad garment shapes and scattered crack marks substitute for convincing folds and painterly detail.

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 Fable 5.1GPT 6 Luna
Prompt & likeness6.0/107.0/10
Anatomy & construction5.0/106.0/10
Space & placement6.0/107.0/10
Light & reflections6.0/106.0/10
Purposeful detail5.0/106.0/10
Artistry & character5.5/106.5/10
Materials & effects5.5/105.5/10
Visual integrity6.5/108.0/10

Raccoon

Same prompt

Claude Fable 5.170.8/100

Claude Fable 5.1: Raccoon SVG benchmark
Researcher observations

The raccoon rides on the dog's back, and the dog's extended foreleg reaches the jet ski controls. Expressive faces, a clear silhouette and sweeping spray make the action readable. Limb and handlebar overlaps weaken construction; broad shading provides limited volume, and the glowing sun has little corresponding reflection on the water. Clean vector shapes support an appealing but simplified illustration.

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 Fable 5.1GPT 6 Luna
Prompt & likeness8.5/108.0/10
Anatomy & construction6.5/106.5/10
Space & placement7.0/107.5/10
Light & reflections5.5/106.0/10
Purposeful detail7.0/107.0/10
Artistry & character7.5/108.0/10
Materials & effects6.5/106.5/10
Visual integrity7.5/108.0/10

Pelican

Benchmax control

Outside General and Visual Intelligence.

Claude Fable 5.172.3/100

Claude Fable 5.1: Pelican SVG benchmark
Researcher observations

The pelican reads clearly, with an expressive face, prominent bill and appealing composition. Both legs connect to the body, but the far foot's pedal contact and the wing's steering grip remain unclear. Wheel alignment and background layers are coherent. Clean contours and feather lines give polish, while schematic machinery, limited surface texture and weak directional lighting constrain the finish.

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 Fable 5.1GPT 6 Luna
Prompt & likeness8.5/108.0/10
Anatomy & construction6.5/106.0/10
Space & placement7.5/106.5/10
Light & reflections6.0/106.5/10
Purposeful detail7.0/107.5/10
Artistry & character7.5/108.0/10
Materials & effects6.0/106.5/10
Visual integrity8.0/108.0/10