STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Muse Spark 1.3 vs Muse Spark Open

Muse Spark Open leads Muse Spark 1.3 by 4.3 points on StealthMark, 44.1 to 39.8. It leads on 5 of 9 benchmarks, including Latch, and Muse Spark 1.3 on 4, including Foresight. Muse Spark Open scores higher on Ground Truth.

See the difference ↘
All results ↗
All results ↗

Overall StealthMark

39.8/100Overall rank 34/53
44.1/100Overall rank 29/53

General Intelligence

38.3/100
42.6/100

Visual Intelligence

42.3/100
46.6/100

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

  • Muse Spark Open

Open or local

BENCHMARK BY BENCHMARK

Where each model leads

  • Muse Spark 1.3
  • Muse Spark Open
  • Other models
  • Median

DATASHEET

Specs and pricing

Muse Spark Open scores higher on StealthMark and runs 12% faster in our speed test. Both take about 1M tokens of context.

  • Muse Spark 1.3
  • Muse Spark Open
  • Other models
  • Median
PricePer 1M output tokens, input below
Muse Spark 1.3: $4.25Tied$1.25 inputMuse Spark Open: $4.25Tied$1.25 input
Context windowTokens per request, max output below
Muse Spark 1.3: 1MTiedMuse Spark Open: 1MTied1M max output
Output speedTokens per second, our measurement
Muse Spark 1.3: 321tokens/sMuse Spark Open: 36112% fastertokens/s
SizeTotal and active parameters
Muse Spark 1.3: Not disclosedMuse Spark Open: 816B42B active
Developer
MetaBoth
Released
2 Sep 202615 Oct 2026
Origin
United StatesBoth
Input → output
Text, image, video, audio, PDF → textText, image, audio, video → text
Architecture
Not publishedSparse mixture-of-experts Transformer with perception encoders; 62 decoder layers, 256 experts with 8 selected per token, grouped-query attention and sliding-window/full-attention layers.

Full datasheets, every price and sourceMuse Spark 1.3 ↗Muse Spark Open ↗

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.

Muse Spark 1.3 64.3/100Rank 6/47

Survived 2 of 3
Foresight: complete playing field
Level 311 ptsTurn 17 / 20

Muse Spark Open 29.4/100Rank 34/47

Survived 0 of 3
Foresight: complete playing field
Level 38 ptsTurn 15 / 20

Points per level

LevelMuse Spark 1.3Muse Spark Open
Level 1Second Thoughts
26 ptsSurvived
4 ptsOut of lives
Level 2Pressure Pot
10 ptsSurvived
9 ptsOut of lives
Level 3Hide or Flight
11 ptsOut of lives
8 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.

Muse Spark 1.3 72.4/100Rank 26/483 of 5 levels

3 of 5 played
Latch: complete playing field
Level 318.8 ptsTurn 32 / 36

Muse Spark Open 75.7/100Rank 12/48

Cleared 5 of 5
Latch: complete playing field
Level 519.6 ptsTurn 32 / 40

Points per level

LevelMuse Spark 1.3Muse Spark Open
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.8 ptsCleared
9.8 ptsCleared
Level 3Relay vault
18.8 ptsCleared
19.2 ptsCleared
Level 4Passing bay
Pending
17.8 ptsClearedFinished early · 1 beacon left
Level 5Second thoughts
Not played
19.6 ptsCleared

Newton's Mirror

Same task instructions

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

The judgment

Muse Spark 1.3

The paint state is incorrectly and poorly drawn, despite a recognizable sphere-and-paint setup. The oversized sphere, oversized compact paint bodies, and blurred wall and floor images further limit the result. Isolated reflection cues provide very little support for the required repeated virtual rooms, nested spherical imagery or emitter mapping.

Muse Spark Open

The airborne black blob and deformed paint support the broad contact sequence, although cyan attachment and wheel-directed transport remain partial. The sphere and black blob have substantial framing errors. The dominant limitation is the largely absent mirror system: faint wall circles and isolated highlights provide little evidence of recursive room geometry or curved nested reflections. Oversized compact paint features and diffuse material treatment further limit credit.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
State at 600 ms6.0/2514.0/25
Camera and placement8.5/156.0/15
Reflections5.5/1208.0/120
Materials and scale4.0/103.5/10
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

Muse Spark 1.3

The luminous creature and geometric mirror counterpart communicate self-recognition through a coherent palette and expressive eyes. The transformed reflection is purposeful. Simple oval anatomy, ambiguous reaching-arm construction, shallow spatial staging and limited illumination of nearby surfaces keep the illustration below exceptional execution.

Muse Spark Open

The rounded silhouette and asymmetric expression make an appealing baby elephant, supported by a quiet background and grounding shadow. The protective action remains difficult to read: forefeet cannot be confidently traced into a grip, and seed contact is crowded by fine lines. Controlled simple shapes provide charm, but limited anatomical clarity, shading and surface detail leave the execution uneven.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
Task & likeness8.0/105.0/10
Anatomy & construction5.0/104.5/10
Space & placement6.5/106.0/10
Light & reflections7.0/105.0/10
Purposeful detail6.5/106.0/10
Artistry & character5.5/105.0/10
Materials & effects6.5/105.0/10
Visual integrity7.5/106.5/10

Benchmark task

Muse Spark 1.3

An imagined creature encounters its reflection. The scene tests original character design, visual self-interpretation and the relationship between a subject and its reflected image.

Muse Spark Open

A small elephant protecting a delicate seed tests expressive anatomy, physical contact and contrasting organic materials.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Muse Spark 1.3

Dark hair, a restrained smile and overlapping hands suggest Mona Lisa, but replication is weak. The face is markedly elongated, the hands are oval pads with faint finger strokes, and the atmospheric landscape is absent. Soft gradients provide basic volume, while the frontal symmetry, shallow space and sparse clothing detail limit the portrait’s drawing quality.

Muse Spark Open

A recognizable, orderly interpretation with clean major contours, connected body forms and modest facial shading. Wide eyes, frontal symmetry and schematic hands limit likeness and expression. Layered scenery establishes basic depth, but shallow arm overlaps, flat clothing and sparse fine detail keep the execution basic and uneven.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
Task & likeness1.0/103.0/10
Anatomy & construction1.5/103.0/10
Space & placement1.5/105.0/10
Light & reflections1.5/104.5/10
Purposeful detail1.0/104.0/10
Artistry & character1.5/103.0/10
Materials & effects1.5/104.0/10
Visual integrity3.0/106.0/10

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

Muse Spark 1.3

The warm sunset, framing palms and colorful beach accessories create an appealing scene with the requested animals, birds and reflections. Construction remains schematic: the raised hand misses the kite string, and a doglike silhouette hangs above the water without clear support. The sun reflection establishes a focal path, but shadows and materials lack depth. An unexplained horizontal bar crosses the sun.

Muse Spark Open

A coherent sunset beach with readable activities, balanced framing and controlled colour transitions. Small accessories add interest, but schematic anatomy, limited surface detail, weak directional shadows and a geometric reflection constrain its finish. Most shapes and overlaps remain clean.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
Task & likeness6.5/108.0/10
Anatomy & construction3.0/106.0/10
Space & placement5.5/106.5/10
Light & reflections6.5/105.5/10
Purposeful detail5.0/106.5/10
Artistry & character3.5/105.5/10
Materials & effects3.0/106.0/10
Visual integrity3.5/108.0/10

Benchmark task

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

Ground Truth

Same task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Muse Spark 1.3

This benchmark has not been assessed yet.

Muse Spark Open

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

Muse Spark 1.3

The raccoon clearly rides on the dog's back, and the dog's paws reach the jet ski controls. Expressive faces and bright colors make the scene appealing. Simplified joints, crowded steering geometry and shallow hull perspective limit construction. The sun has no corresponding water reflection, and the splash shapes convey speed more clearly than convincing displacement.

Muse Spark Open

Expressive faces, distinct accessories and clean color separation make the scene appealing and recognizable. Character detail is stronger than the functional construction: steering contact, limb overlaps and seating remain ambiguous. The readable hull and lively spray establish motion, while limited directional shading and simplified surfaces constrain depth and physical coherence.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
Task & likeness8.5/104.0/10
Anatomy & construction6.5/103.0/10
Space & placement7.0/106.0/10
Light & reflections5.0/104.5/10
Purposeful detail6.5/107.0/10
Artistry & character5.5/103.5/10
Materials & effects6.0/105.0/10
Visual integrity7.5/105.0/10

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

Muse Spark 1.3

The pelican and bicycle are immediately recognizable, with an expressive face, bold bill and cheerful composition. Both legs connect to the body and reach pedal-like supports, but articulation, saddle support and wing contact with the handlebar remain unclear. Wheel alignment and layering are coherent. Simple landscape shapes, generic shadows and limited material variation constrain the finish.

Muse Spark Open

A controlled, appealing cartoon with a recognizable pelican, expressive face and clean curved forms. Feather lines, spokes and bill shading provide useful complexity. Aligned wheels and a ground shadow establish placement, but uncertain pedal contacts and obscured mechanical connections weaken support and riding action. Lighting remains loosely coordinated with the sun.

Score breakdown

CategoryMuse Spark 1.3Muse Spark Open
Task & likeness8.5/107.5/10
Anatomy & construction6.0/105.0/10
Space & placement7.0/106.0/10
Light & reflections6.0/105.0/10
Purposeful detail7.0/106.5/10
Artistry & character5.5/105.5/10
Materials & effects6.5/106.0/10
Visual integrity7.0/107.5/10

Benchmark task

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