NIHSS Stroke Scale Calculator
The National Institutes of Health Stroke Scale (NIHSS) grades the severity of an acute stroke from a standardised neurological examination. It scores items such as level of consciousness, gaze, visual fields, facial palsy, motor and sensory function, language, and neglect. This calculator sums the item scores you enter from a completed examination. The examination itself, and any treatment decisions, must be performed by trained clinicians.
NIHSS total
NIHSS total = sum of all 13 item scores
Items 5 (motor arm) and 6 (motor leg) each combine left and right sides (0 to 4 per side)
Maximum total = 42
Each item is scored from the standardised examination, with the motor arm and motor leg items summing the left and right limbs. The calculator simply totals the values you enter; it does not perform the neurological examination.
Worked example
A patient with mild stroke might score 1 (gaze) + 1 (facial palsy) + 2 (motor arm) + 1 (sensory) + 2 (language) = 7, often classed as moderate severity. Bands commonly cited are 0 (no symptoms), 1 to 4 (minor), 5 to 15 (moderate), 16 to 20 (moderate to severe), and 21 to 42 (severe).
Frequently asked questions
What do NIHSS totals mean?
Commonly cited severity bands are 0 (no stroke symptoms), 1 to 4 (minor), 5 to 15 (moderate), 16 to 20 (moderate to severe), and 21 to 42 (severe). Bands guide communication and trial criteria but do not by themselves dictate treatment.
How are the motor arm and motor leg items scored here?
Each limb scores 0 to 4 in the full scale. This calculator asks for the combined left plus right total for the arms (0 to 8) and for the legs (0 to 8). Enter the sum of both sides for each.
Can I use this to diagnose a stroke?
No. The NIHSS quantifies the severity of a stroke that has been examined by a trained clinician. It is not a diagnostic test and does not replace imaging or clinical assessment.
Who should perform the NIHSS?
The scale is designed to be administered by clinicians trained and certified in its use, to keep scoring consistent. This tool only adds up scores from such an examination.
Sources
- U.S. National Institute of Neurological Disorders and Stroke: Stroke information.
- U.S. National Library of Medicine, StatPearls: National Institutes of Health Stroke Scale.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. Educational tool, not medical advice. See our methodology.