NIHSS Calculator (NIH Stroke Scale)

The adult NIHSS is a standardized examination that quantifies neurological deficits observed during one examination. It supports documentation, communication, and serial assessment; it is not a stroke screening or diagnostic test and does not itself prove or exclude stroke.

Sources: [1, 4, 6]

The 15 entries cover consciousness, LOC questions and commands, gaze, visual fields, facial palsy, both arms, both legs, limb ataxia, sensation, language, dysarthria, and extinction or inattention. A complete numeric total is the sum of all 15 entries and ranges from 0 to 42.

Sources: [1, 6]

No. A score of 0 means no deficit was scored on these NIHSS items during that examination. It does not exclude stroke, including deficits that the scale may underrepresent.

Sources: [5, 12, 13]

No. NIHSS is a standardized neurological-deficit assessment, not a screening or diagnostic test. Diagnosis requires the complete clinical assessment and, when appropriate, imaging and other investigations.

Sources: [5, 6]

The same total can arise from very different deficits. The complete item breakdown preserves clinically important detail, including potentially disabling aphasia, hemianopia, or dominant-hand weakness that may occur with a low total.

Sources: [4, 5]

Use the formal item order and standardized training. Record the patient’s actual performance without repeated coaching, the examination time, language or hearing factors, prior deficits, sedation, intubation, and physical barriers. Serial scores should note factors that affect comparability.

Sources: [2, 3, 7]

UN documents a specific NINDS-permitted limitation, not uncertainty, poor cooperation, aphasia, sleepiness, or an omitted examination. Only both arms, both legs, limb ataxia, and dysarthria allow UN, and a reason is required: for motor arm, motor leg, and limb ataxia the permitted reason is amputation or joint fusion; for dysarthria it is intubation or another physical barrier to speech production. Intubation can make dysarthria legitimately UN; aphasia alone does not. LOC Questions and the other non-permitted items do not allow UN.

Sources: [6, 8, 9, 10, 11]

UN is never treated as 0. If a permitted item is untestable, this page reports only the partial scored-item sum and withholds the complete 0–42 total. The partial sum is not a complete NIHSS total and must be documented with the untestable item and reason.

Sources: [6, 7]

These factors require standardized administration and explicit documentation. Intubation or another physical barrier to speech production can make dysarthria UN, but aphasia does not automatically make dysarthria UN. Language barriers, sedation, hearing, and prior deficits may affect interpretation and comparability; they do not create a general UN option.

Sources: [3, 7, 11]

No. NIHSS cannot alone determine intravenous thrombolysis or mechanical thrombectomy. Decisions require diagnosis, imaging, symptom onset and last-known-well time, contraindications, vascular findings, and stroke-team assessment. This calculator does not execute a treatment algorithm.

Sources: [4, 5]

Posterior-circulation, brainstem, cerebellar, gait, some cranial-nerve, and some right-hemisphere cognitive, behavioral, or spatial deficits may be underrepresented. A low total does not make these findings unimportant.

Sources: [4, 13]

No. This page is for the adult NIHSS. PedNIHSS is different and should not be substituted automatically for the adult scale.

Sources: [6, 14]