NIH Stroke Scale Calculator

The National Institutes of Health Stroke Scale, commonly abbreviated NIHSS, is a structured neurological examination used to describe deficits associated with acute stroke. It assesses consciousness, responses to questions and commands, gaze, visual fields, facial movement, motor function in each arm and leg, limb ataxia, sensation, language, speech clarity, and extinction or inattention. Individual item scores are added to produce a total from zero to 42, with higher totals generally representing more extensive observed neurological impairment. This calculator performs the arithmetic after a trained examiner assigns each item score. It does not determine the item values from symptoms and cannot guide an untrained person through the examination. Each field displays the allowed minimum and maximum. Motor function is scored separately for the left and right arms and legs, which is why the 11 named sections appear as 15 numeric entries. The conventional descriptive bands shown here are zero for no scored symptoms, 1 to 4 for minor stroke, 5 to 15 for moderate stroke, 16 to 20 for moderate to severe stroke, and 21 to 42 for severe stroke. A total score is useful for communication, treatment research, serial examinations, and broad prognosis, but it does not capture every clinically important deficit. Posterior circulation strokes, disabling hand weakness, gait impairment, or isolated language problems may produce a comparatively low total. Sedation, intubation, language barriers, preexisting disability, and an incomplete examination can also affect scoring. Examiners should follow the official instructions, score what the patient does rather than what they believe the patient could do, and document items that cannot be tested according to protocol. Stroke is a medical emergency. Sudden facial droop, arm weakness, speech difficulty, vision loss, severe imbalance, or another acute neurological change requires immediate emergency response even if the calculated score is low or zero. Treatment eligibility depends on symptom onset or last-known-well time, imaging, contraindications, functional significance, and specialist assessment, not on the NIHSS total alone. Use this page only to add scores already obtained through a standardized clinical examination. It does not diagnose stroke, exclude hemorrhage, select thrombolysis or thrombectomy, replace imaging, or substitute for local stroke pathways and qualified medical judgment.