HealthFree

NIHSS Calculator

NIH Stroke Scale calculator online: sum all 15 NIHSS items for a total from 0 to 42. Used in emergency departments and stroke units for severity, treatment eligibility, and serial monitoring. Training and local protocols still apply.

Enter Values

Result

Enter values above and click Calculate to see your result.

AI Assistant

Ask about this calculator

I can help you understand the nihss calculator formula, interpret your results, and answer follow-up questions.

Try asking

Our AI assistant provides general estimates and advice only. Please consult a qualified healthcare professional before making any health-related decisions.

Formula

1
NIHSS total = sum of items 1a through 11 (motor arms and legs scored separately).
2
Higher score = more severe stroke-related deficit.

How it works: Each item uses the standard NIHSS response definitions. This page adds points exactly as selected; it does not replace formal certification or filmed assessment for research.

Worked Example

If every item is scored 0, total NIHSS is 0. A focal deficit might yield totals in the 4 to 15 range depending on findings.

Using NIHSS in practice

The NIH Stroke Scale is the standard quantitative exam for acute ischemic stroke. Teams use it at baseline, after treatment, and on schedule for neurologic change.

  • Scores roughly below 5 often correlate with mild deficits, but treatment decisions are not based on a single cutoff
  • Large shifts in NIHSS may prompt imaging or blood pressure changes per protocol
  • Posterior circulation strokes may have lower NIHSS despite dangerous infarcts
  • Formal training improves inter-rater reliability

Match your documentation to hospital stroke order sets. This calculator only adds the numbers you select.

You can also calculate changes using our Wells Score (DVT and PE), CHA2DS2-VASc Score or PERC Rule Calculator.

Frequently Asked Questions

Is this NIHSS certificate training?

No. It is a worksheet-style sum. Certification courses use video cases and proctored exams.

What is a severe NIHSS?

Totals above roughly 20 are often described as severe, but labels vary by study. Large artery occlusion can occur at many NIHSS levels.

Can NIHSS be 0 with a stroke on MRI?

Rarely, very small or posterior lesions may produce minimal exam findings early. Clinical suspicion and imaging still guide care.

Do I score the worst side for motor items?

Follow the official NIHSS instructions for each limb. This tool stores one score per item as you enter it.

Why 42 as maximum?

Each item has its own cap; the valid total range is 0 through 42 on the standard scale.

Does NIHSS replace ASPECTS or imaging?

No. ASPECTS, CTA, and perfusion imaging answer different questions about tissue and vessels.

Who should document NIHSS?

Stroke-certified nurses and physicians often document per facility policy. Trainees should be supervised until proficient.

Medical Disclaimer

This calculator is provided for informational and educational purposes only. It is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making any decisions based on these results. Do not disregard or delay seeking medical advice because of information obtained from this tool.

Secure and Private

All calculations run locally. Your data never leaves your browser.

Precise Calculations Powered by Calculory AI