About the Glasgow Coma Scale Calculator
The Glasgow Coma Scale (GCS) describes a patient’s level of consciousness by scoring three responses: eye opening (1–4), verbal response (1–5) and best motor response (1–6). It was described by Graham Teasdale and Bryan Jennett in 1974 for patients with acute brain injury and is now used worldwide in emergency departments, ambulances, intensive care and neurosurgery. This calculator adds the components into the GCS score (3–15), writes the standard notation such as "E3 V4 M6", and classifies severity.
It is designed for paramedics, nurses, doctors and students who want a quick, correctly formatted result, and for anyone trying to understand a GCS reported for a family member. Option labels follow the current terminology from the official Glasgow Structured Approach (for example "to pressure" rather than "to pain").
When a component cannot be assessed — eyes swollen shut, an intubated airway, or paralysis — mark it "NT" (not testable). In that case no total is calculated, because adding an assumed value would be misleading; report the components instead. You can also record pupil reactivity to obtain the GCS-Pupils (GCS-P) score.
With the default inputs, the glasgow coma scale score is 13 / 15. Change any value above to recalculate instantly.
How to use the glasgow coma scale calculator
- 1Check for factors that interfere with assessment (sedation, intubation, swelling, hearing loss).
- 2Observe eye opening: spontaneous, then to sound, then to fingertip pressure.
- 3Assess speech: orientation to name, place and date.
- 4Assess the best motor response: commands first, then response to pressure.
- 5Select each response (or NT), and optionally record pupil reactivity for GCS-P.
- 6Report the components with the total, e.g. "GCS 13 (E3 V4 M6)".
Formula and method
Each component is scored at the best response observed: eye opening from 1 (none) to 4 (spontaneous), verbal response from 1 (none) to 5 (orientated) and motor response from 1 (none) to 6 (obeys commands). The GCS score is their sum, from 3 to 15. Head injuries are conventionally classified as mild (13–15), moderate (9–12) or severe (3–8).
The GCS-Pupils score, introduced in 2018 using data from the IMPACT and CRASH head-injury databases, subtracts the Pupil Reactivity Score — the number of pupils (0, 1 or 2) that do not react to light — from the GCS total, extending the range down to 1. If any component is not testable, no total is produced.
- E
- Eye opening, 1–4
- V
- Verbal response, 1–5 (T if intubated)
- M
- Best motor response, 1–6
- PRS
- Pupil Reactivity Score: number of pupils unreactive to light (0–2)
Worked examples
Confused patient after a fall
Eyes open to voice (3), confused conversation (4) and obeying commands (6) give 3 + 4 + 6 = 13, reported as "GCS 13 (E3 V4 M6)" — a mild head-injury score. Both pupils react, so the GCS-P is also 13.
Severe injury with one unreactive pupil
No eye opening (1), sounds only (2) and normal flexion to pressure (4) total 7, a severe score. One pupil does not react, so the Pupil Reactivity Score is 1 and GCS-P = 7 − 1 = 6.
Intubated patient
With an endotracheal tube the verbal response cannot be tested, so it is recorded as "VT". Rather than guessing a total, the result is reported as the components "E2 VT M5".
Frequently asked questions
What is a normal GCS score?+
A fully alert, orientated person who obeys commands scores the maximum of 15 (E4 V5 M6). The lowest possible score is 3, meaning no eye, verbal or motor response.
What GCS score means coma?+
A GCS of 8 or less is the widely used definition of coma and of severe brain injury. Scores of 9–12 indicate moderate and 13–15 mild impairment.
How do you score GCS in an intubated patient?+
The verbal response cannot be tested, so it is recorded as "T" (e.g. E3 VT M5). Best practice is to report the components rather than inventing a total.
Why report the components and not just the total?+
The same total can describe very different patients — E4 V1 M6 and E1 V4 M4 both equal 11. The components, especially motor response, carry more clinical information and track change better.
What is the GCS-P score?+
GCS-P combines the GCS with pupil reactivity: subtract 1 for each pupil that does not react to light. It was published in 2018 and improves outcome prediction after head injury.
Can the GCS be used for children?+
The adult verbal scale does not suit pre-verbal children, so modified paediatric versions with age-appropriate verbal responses are used for young children.
For healthcare professionals and education only. This calculator implements a published formula or score but is not a diagnosis and does not replace clinical judgment. Verify inputs and results against the original source before using them in patient care.