What is the range of the Glasgow Coma Scale?

The total runs from 3 to 15. It is the sum of three components: eye opening scored 1 to 4, verbal response 1 to 5, and motor response 1 to 6. A fully alert person scores 15, and the lowest possible score is 3, not 0.

How is GCS severity classified?

By convention, a total of 13 to 15 indicates mild brain injury, 9 to 12 indicates moderate, and 3 to 8 indicates severe injury. A score of 8 or below usually prompts consideration of airway protection. The tool labels the band for you.

Why report E, V, and M separately?

Two patients with the same total can be clinically very different, so guidelines recommend recording the component scores, for example E3 V4 M5, alongside the total. The tool always shows the E-V-M breakdown, not just the sum.

What if the patient is intubated?

An intubated patient cannot give a verbal response, so the verbal score is recorded as 1T, with T meaning tube. The total is then a non-verbal estimate. The tool reminds you to note this when the verbal score is set to its lowest value.

Does it store patient information?

No. The scoring runs entirely in your browser. Your selections are never transmitted to or saved on any server.

What is the Glasgow Coma Scale (GCS) Calculator?

Score the Glasgow Coma Scale by selecting eye-opening, verbal, and motor responses, and read the total from 3 to 15 with a mild, moderate, or severe brain-injury band and the E-V-M breakdown. Runs in your browser. It runs free in your browser on Gera Tools, with nothing uploaded.

Glasgow Coma Scale (GCS) Calculator

Name: Glasgow Coma Scale (GCS) Calculator
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

The Glasgow Coma Scale (GCS) is the standard structured way to describe and communicate a patient’s level of consciousness after head injury, medical illness, or resuscitation. This calculator scores all three components and bands the total by injury severity — useful for learning the scale, teaching, or double-checking your own scoring before documentation.

The three components in detail

The GCS rates the best response the patient is able to give in each of three categories:

Eye opening (E, 1–4)

Score	Response
4	Spontaneous — eyes open without any stimulus
3	To speech — eyes open to verbal command or name
2	To pain — eyes open only to painful stimulus
1	None — no eye opening to any stimulus

Verbal response (V, 1–5)

Score	Response
5	Oriented — knows who, where, and when; coherent conversation
4	Confused — converses but disoriented or confused
3	Words — intelligible words but no sustained conversation
2	Sounds — moans, groans, incomprehensible sounds
1	None — no verbal response

Motor response (M, 1–6)

Score	Response
6	Obeys commands — follows two-stage verbal commands
5	Localises to pain — purposeful movement toward painful stimulus
4	Withdrawal — pulls away from pain non-purposefully
3	Abnormal flexion — stereotyped flexion (decorticate posturing)
2	Extension — stereotyped extension (decerebrate posturing)
1	None — no motor response to pain

The motor response is the most clinically informative of the three components. Flexion (3) and extension (2) responses indicate significant brainstem compromise.

How the total and severity bands work

Total = Eye + Verbal + Motor   →  range 3 to 15

The minimum is 3 (not 0 — the scale starts at 1 in each component) and the maximum is 15 (full consciousness). Severity is conventionally banded:

13–15: Mild brain injury
9–12: Moderate brain injury
3–8: Severe brain injury — GCS of 8 or below is the traditional threshold prompting consideration of airway protection

Worked example

A patient who opens eyes to speech (E3), is confused in conversation (V4), and localises their hand to a painful stimulus (M5):

Total: 3 + 4 + 5 = 12
Reported as: E3 V4 M5, GCS 12 — Moderate

Another patient with spontaneous eye opening (E4), oriented speech (V5), and obeying commands (M6): Total = 15 — fully alert.

Why always record E, V, M separately

Two patients can share the same total but have very different clinical pictures. A score of 9 could be E3 V2 M4 (opens eyes to voice, incomprehensible, withdraws) or E1 V3 M5 (no eye opening, confused words, localises). Clinical decision-making differs between these. International guidelines recommend recording the component breakdown alongside the total: for example, E3 V4 M5 = GCS 12, not simply “GCS 12”.

Special situations

Intubated patients — cannot give a verbal response. Record verbal as T (tube), so the component becomes V1T. The total is then qualified: “GCS 9T” indicates a non-verbal assessment.

Orbital swelling or eye injuries — if the patient cannot open their eyes due to physical injury, note this rather than scoring as eye opening 1 (none). Document as EC (eye closed due to swelling).

Children under 5 — paediatric GCS modifications exist for pre-verbal children; this calculator applies the adult scale.

This tool is an educational aid that runs locally in your browser. Clinical decisions must be made by qualified healthcare professionals based on the full patient assessment.