NIHSS Stroke Scale Calculator
Calculate the NIH Stroke Scale (NIHSS) score across 11 neurological domains to quantify stroke severity. A standardized research and clinical-education reference — not a substitute for bedside neurological assessment.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| NIHSS Stroke Scale Calculator | — | NIHSS = sum of 11 item scores (0–42) | points |
Step-by-Step Examples
Alert, all questions correct, mild facial droop (1), mild arm drift (1), mild dysarthria (1).
- LOC items 1a+1b+1c = 0
- Facial palsy = 1, motor arm = 1, dysarthria = 1
- All other items = 0
- Total = 3
Not alert but arousable (1), one question correct (1), partial hemianopia (1), partial facial paralysis (2), arm no effort against gravity (3), leg drift (1), severe sensory loss (2), severe aphasia (2).
- 1a=1, 1b=1, 1c=0
- Visual=1, facial=2
- Motor arm=3, motor leg=1
- Sensory=2, language=2
- Total = 13
Unresponsive (3), neither question correct (2), neither command (2), forced gaze deviation (2), complete hemianopia (2), complete facial paralysis (3), no arm movement (4), no leg movement (4), total sensory loss (2), mute (3), anarthric (2), complete neglect (2).
- LOC cluster = 3+2+2 = 7
- Gaze 2 + visual 2 + facial 3 = 7
- Motor arm 4 + leg 4 = 8
- Sensory 2 + language 3 + dysarthria 2 + neglect 2 = 9
- Ataxia untestable = 0
- Total = 31
Real-World Applications
Common Mistakes to Avoid
NIHSS scores observed performance, not inferred ability. If the patient does not perform the task, it scores as a deficit even when you suspect they could.
Language items carry heavy weight, so left-hemisphere strokes score higher than right-hemisphere strokes of similar tissue volume. A low score does not mean a small stroke.
This tool arithmetically totals items you enter. The clinical value lives entirely in a trained examiner performing the actual assessment.