| L1 Morphological Fidelity | Body form, skeleton, anatomical structure | Does it look like a human? | Body proportion · Skeletal structure · Joint axes · Muscle layout · Facial proportion |
| L2 Biomechanical Fidelity | The motion system | Does it move like a human? | Range of motion · Gait · Postural stability · Joint torque · Energy consumption · Motion smoothness |
| L3 Biophysical Fidelity | Skin, soft tissue, temperature, contact | Does it feel like a human? | Young's modulus · Rebound · Surface temperature · Coefficient of friction · Skin texture |
| L4 Sensorimotor Fidelity | Perception and bodily feedback | Does it sense its own body the way a human does? | Tactile density · Visual coverage · Proprioception · State estimation · Response latency |
| L5 Expressive Fidelity | Expression, gaze, voice, posture | Can it express human emotion? | Expression accuracy · Vocal affect · Gaze naturalness · Lip-sync · Gestural semantic consistency |
| L6 Social Fidelity | Long-horizon interaction | Is it treated as a real person? | Trust score · Uncanny valley · Likability · Persona consistency · Long-term acceptance |