STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Claude Fable 5.1 vs Claude Sonnet 5.5

Claude Sonnet 5.5 scores 0.6 points higher overall (62.7 vs 62.1). Claude Fable 5.1 leads General Intelligence; Claude Sonnet 5.5 leads Visual Intelligence. Claude Fable 5.1 scores higher on Newton's Mirror, with its largest category advantage in reflections.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

62.1/100
62.7/100

General Intelligence

54.3/100
45.2/100

Visual Intelligence

67.7/100
76.1/100

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.

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.

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
State at 600 ms24.0/2525.0/25
Camera and placement14.0/1515.0/15
Reflections48.0/12023.5/120
Materials and scale7.0/1010.0/10
Floor-damage reward0.0/100.0/10

Selfie

Same prompt

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.

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.

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
Prompt & likeness6.5/108.0/10
Anatomy & construction6.5/108.0/10
Space & placement7.5/108.0/10
Light & reflections6.5/107.5/10
Purposeful detail6.0/107.5/10
Artistry & character7.5/108.0/10
Materials & effects6.5/107.0/10
Visual integrity8.0/108.5/10

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

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

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
Prompt & likeness8.5/109.0/10
Anatomy & construction7.0/107.0/10
Space & placement7.0/108.5/10
Light & reflections7.0/107.5/10
Purposeful detail7.5/109.0/10
Artistry & character8.0/109.5/10
Materials & effects6.5/107.5/10
Visual integrity8.0/107.5/10

Mona Lisa

Different prompts

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

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

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
Prompt & likeness6.0/107.0/10
Anatomy & construction5.0/106.0/10
Space & placement6.0/106.5/10
Light & reflections6.0/106.5/10
Purposeful detail5.0/106.0/10
Artistry & character5.5/106.5/10
Materials & effects5.5/105.5/10
Visual integrity6.5/106.5/10

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

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

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
Prompt & likeness8.5/108.5/10
Anatomy & construction6.5/107.0/10
Space & placement7.0/107.5/10
Light & reflections5.5/106.5/10
Purposeful detail7.0/108.0/10
Artistry & character7.5/108.0/10
Materials & effects6.5/107.5/10
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

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

Compare category scores
CategoryClaude Fable 5.1Claude Sonnet 5.5
Prompt & likeness8.5/109.0/10
Anatomy & construction6.5/107.5/10
Space & placement7.5/107.5/10
Light & reflections6.0/106.5/10
Purposeful detail7.0/108.0/10
Artistry & character7.5/107.5/10
Materials & effects6.0/106.5/10
Visual integrity8.0/108.0/10