Glasgow Coma Scale Calculator
The Glasgow Coma Scale measures level of consciousness from three responses: eye opening, verbal response and best motor response. Select the best response observed for each. The official guidance is to report the three components, not just the total.
| Result | Interpretation |
|---|---|
| 3 to 8 | Severe (3 to 8) |
| 9 to 12 | Moderate (9 to 12) |
| 13 to 15 | Mild (13 to 15) |
Source: Teasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet 1974;2(7872):81-84. (doi:10.1016/s0140-6736(74)91639-0); Teasdale G, Maas A, Lecky F, et al. The Glasgow Coma Scale at 40 years: standing the test of time. Lancet Neurol 2014;13(8):844-854. (doi:10.1016/S1474-4422(14)70120-6); Glasgow Coma Scale © University of Glasgow; GCS Aid descriptors © Sir Graham Teasdale 2015 (glasgowcomascale.org).
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The three components
The GCS adds the best response seen in each of three areas, for a total of 3 to 15.
| Component | Response | Points |
|---|---|---|
| Eye opening (E) | Spontaneous | 4 |
| To sound | 3 | |
| To pressure | 2 | |
| None | 1 | |
| Verbal (V) | Orientated | 5 |
| Confused | 4 | |
| Words | 3 | |
| Sounds | 2 | |
| None | 1 | |
| Motor (M) | Obeys commands | 6 |
| Localising | 5 | |
| Normal flexion | 4 | |
| Abnormal flexion | 3 | |
| Extension | 2 | |
| None | 1 |
The structured version of the scale replaced older wording: eye opening “to pressure” replaced “to pain”, and “inappropriate words” and “incomprehensible sounds” became “words” and “sounds”.
Report the components, not just the total
The scale’s authors recommend describing a person by the three components, written for example as E3 V4 M6, and keeping the total for describing groups of patients. Two people with a total of 9 can be in very different states, depending on which responses are missing.
If a component cannot be tested, such as speech in someone with a breathing tube, it is recorded as NT (not testable), not as 1. The official guidance is not to report a total at all in that case, because a falsely low score can make someone look more unwell than they are. Follow the components that can be tested.
Head injury severity
| Total GCS | Traditional severity |
|---|---|
| 13 to 15 | Mild |
| 9 to 12 | Moderate |
| 3 to 8 | Severe |
These are the bands most commonly used to classify traumatic brain injury. A 2025 NIH-led initiative has proposed a fuller system that adds blood biomarkers and imaging, to characterize injuries more accurately than the GCS total alone.
FAQs
What is a normal GCS score?
15, which means the person opens their eyes spontaneously, is fully orientated and obeys commands.
What GCS score is severe?
A total of 3 to 8 falls in the traditional “severe” category for head injury, 9 to 12 is moderate, and 13 to 15 is mild.
How do you score GCS in an intubated patient?
Record the verbal component as NT (not testable) and assess eye and motor responses. Do not add up a total.
The Glasgow Coma Scale is © University of Glasgow. The structured descriptors are from the GCS Aid, © Sir Graham Teasdale 2015 (glasgowcomascale.org).