STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Claude Opus 5.5 vs Iceman Contributor

Claude Opus 5.5 leads Iceman Contributor by 53.4 points on StealthMark, 72.6 to 19.2. It leads on all 9 benchmarks. Claude Opus 5.5 scores higher on Newton's Mirror, with its largest category advantage in reflections.

See the difference ↘
All results ↗
Model guide ↗

Overall StealthMark

72.6/100Overall rank 2/53
19.2/100Overall rank 47/53

General Intelligence

71.3/100
11.7/100

Visual Intelligence

75.0/100
31.0/100

Reasoning efficiency

On every task, result quality and reasoning tokens are each compared with all measured models and weighed equally. Each dot is one model.

Single-step reasoning Result quality weighed against reasoning tokens on a single problem

Multi-step reasoning Result quality weighed against reasoning tokens across connected steps, as in agentic workflows

  • Claude Opus 5.5

Open or local

BENCHMARK BY BENCHMARK

Where each model leads

  • Claude Opus 5.5
  • Iceman Contributor
  • Other models
  • Median

DATASHEET

Specs and pricing

Claude Opus 5.5 scores higher on StealthMark and runs 3.6× faster in our speed test.

  • Claude Opus 5.5
  • Iceman Contributor
  • Other models
  • Median
PricePer 1M output tokens, input below
Claude Opus 5.5: $20$4 inputIceman Contributor: No list price
Context windowTokens per request, max output below
Claude Opus 5.5: 1M128K max outputIceman Contributor: Not published
Output speedTokens per second, our measurement
Claude Opus 5.5: 1663.6× fastertokens/sIceman Contributor: 46tokens/s
Developer
AnthropicNot published
Released
22 Sep 2026Not published
Origin
United StatesNot published
Input → output
Text, image → textNot published

Full datasheets, every price and sourceClaude Opus 5.5 ↗

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.

Claude Opus 5.5 66.3/100Rank 5/47

Survived 3 of 3
Foresight: complete playing field
Level 39 ptsTurn 20 / 20

Iceman Contributor 3.2/100Rank 47/47

Survived 0 of 3
Foresight: complete playing field
Level 31 ptsTurn 7 / 20

Points per level

LevelClaude Opus 5.5Iceman Contributor
Level 1Second Thoughts
27 ptsSurvived
0 ptsOut of lives
Level 2Pressure Pot
11 ptsSurvived
3 ptsOut of lives
Level 3Hide or Flight
9 ptsSurvived
1 ptsOut of lives

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.

Claude Opus 5.5 87.6/100Rank 1/48

Cleared 5 of 5
Latch: complete playing field
Level 520.6 ptsTurn 27 / 40

Iceman Contributor 3.6/100Rank 44/48

Cleared 1 of 5
Latch: complete playing field
Level 55 ptsTurn 25 / 40

Points per level

LevelClaude Opus 5.5Iceman Contributor
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
10.2 ptsClearedFinished early · 1 beacon left
2.8 ptsFinished early
Level 3Relay vault
19.2 ptsCleared
2.2 ptsFinished early
Level 4Passing bay
18.2 ptsClearedFinished early · 3 beacons left
4 ptsFinished early
Level 5Second thoughts
20.6 ptsCleared
5 ptsFinished early

Newton's Mirror

Same task instructions

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

The judgment

Claude Opus 5.5

Open lateral sightlines, first reflected silhouettes and near-field planar panel placement are convincing. Missing outer chains, truncated repetitions and absent nested spherical room and emitter imagery remain the main weaknesses.

Iceman Contributor

The image provides limited evidence through rounded volume, faint wall strips and floor echoes. Its main sphere is small and low, the paint beads do not establish the required interaction history, and most of the defining mirror structure is missing.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
State at 600 ms24.0/250.5/25
Camera and placement15.0/152.5/15
Reflections55.0/1207.5/120
Materials and scale9.0/103.0/10
Floor-damage reward0.0/100.0/10

Benchmark task

A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.

Selfie

Different task instructions

Visual construction and creative interpretation.

The judgment

Claude Opus 5.5

The centered coral squid has a friendly, restrained expression and a balanced radial silhouette within a cream arch. Smooth curves and soft shading give it an appealing matte finish. The mantle is more elongated than compact, the upper arms are visually ambiguous, and the two hanging tentacles read somewhat like legs. Clean execution supports a strong stylized illustration.

Iceman Contributor

The crystal crown, cyan eyes and blue faceting communicate an icy fantasy character. Anatomical readability is substantially weaker: the ringed torso, crowded facial construction and fingerless appendages do not resolve the requested childlike crouch or pouncing gesture. Sparse surface detail and shallow shading further limit the result.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
Task & likeness8.0/104.0/10
Anatomy & construction7.5/103.0/10
Space & placement8.0/104.0/10
Light & reflections7.5/104.5/10
Purposeful detail7.0/104.0/10
Artistry & character7.0/104.5/10
Materials & effects7.0/104.5/10
Visual integrity8.5/104.0/10

Benchmark task

Claude Opus 5.5

A coral squid with spreading arms tests connected anatomy, balanced composition and soft surface shading.

Iceman Contributor

Character scenes test expression, anatomy, materials and coherent visual construction.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Claude Opus 5.5

The portrait preserves the recognizable composition, dark veil, folded hands and distant landscape. Replication is limited by the elongated face and neck, conspicuous eyes and simplified smile. Hands remain connected but their rounded fingers and wrists lack convincing anatomy. Restrained colors create cohesion; shallow modeling and pervasive mottling weaken volume and painterly subtlety.

Iceman Contributor

The portrait retains a dark silhouette against an earthy landscape, but replication is weak. The frontal body, elongated facial proportions and undifferentiated hands lose the reference's defining pose and likeness. Basic gradients and layered hills provide some coherence, with little anatomical or painterly detail.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
Task & likeness6.5/101.5/10
Anatomy & construction5.5/101.5/10
Space & placement6.5/102.5/10
Light & reflections6.5/102.0/10
Purposeful detail6.5/102.0/10
Artistry & character6.0/102.0/10
Materials & effects7.0/102.0/10
Visual integrity7.0/103.0/10

Benchmark task

An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.

Beach

Different task instructions

Creativity, perspective and visual beauty.

The judgment

Claude Opus 5.5

A lively, well-composed beach illustration with rich sunset colors, recognizable animals and appealing accessories. The sun reflection establishes a strong central focus. Clean silhouettes and small details reward inspection, though simplified animal construction, uneven contact shadows and mostly flat materials limit depth and realism.

Iceman Contributor

A coherent sunset beach with recognizable animals, playful details and effective palm framing. Connected silhouettes and layered scenery support modest construction and placement credit. Jointless figures, limited foreshortening and an inadequately separated sun and reflection keep the execution basic despite its attractive color.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
Task & likeness8.5/107.0/10
Anatomy & construction7.5/103.5/10
Space & placement7.0/106.0/10
Light & reflections7.5/104.0/10
Purposeful detail7.5/105.5/10
Artistry & character8.0/103.5/10
Materials & effects6.5/104.5/10
Visual integrity8.0/105.0/10

Benchmark task

A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.

Ground Truth

Different task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Claude Opus 5.5

This benchmark has not been assessed yet.

Iceman Contributor

This benchmark has not been assessed yet.

Benchmark task

A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.

Raccoon

Different task instructions

Scene composition and interacting subjects.

The judgment

Claude Opus 5.5

The masked raccoon clearly rides the dog's back, and the dog's forward paw reaches the steering grip. Expressive faces, vivid colors and sweeping wakes create an appealing illustration. Connected limbs remain schematic, as does the small steering assembly. The broad hull and flat foam weaken water contact; the glowing sun lacks a corresponding reflection or convincing cast shadows.

Iceman Contributor

The sunset palette and red hull establish an appealing setting, but the central interaction remains unresolved. Overlapping bodies obscure the dog, supported seating is unclear, and no readable paw-to-control grip demonstrates steering. Simple construction, weak environmental lighting and loosely described spray limit depth and finish.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
Task & likeness8.5/102.0/10
Anatomy & construction7.5/103.0/10
Space & placement7.5/103.0/10
Light & reflections6.0/104.0/10
Purposeful detail8.5/103.5/10
Artistry & character7.0/102.5/10
Materials & effects7.0/104.0/10
Visual integrity8.0/102.5/10

Benchmark task

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.

Pelican

Different task instructions

Subject construction and spatial relationships.

The judgment

Claude Opus 5.5

The recognizable pelican, orderly bicycle wheels and harmonious sunset create an appealing illustration. Both legs connect to the body and reach pedals; no clear detached or inverted parts appear. Steering contact and seating support are less convincing, while the drivetrain remains schematic. Crisp outlines give a clean finish, but limited shading and flat surfaces leave the scene with modest depth.

Iceman Contributor

A recognizable pelican and bicycle sit within an appealing sunset composition. Feather contours, bill shape and atmospheric colour provide character, but disconnected-looking leg origins, unclear pedal contact and unresolved steering weaken the central riding action. Consistent wheel alignment establishes a side view without resolving the rider's support.

Score breakdown

CategoryClaude Opus 5.5Iceman Contributor
Task & likeness8.5/104.0/10
Anatomy & construction8.0/103.5/10
Space & placement7.0/103.5/10
Light & reflections6.0/105.0/10
Purposeful detail8.0/104.5/10
Artistry & character7.5/103.5/10
Materials & effects6.0/104.0/10
Visual integrity8.5/103.0/10

Benchmark task

A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.