Frailty Index Calculator
Estimate a simple frailty index and Fried phenotype category from five yes/no criteria used in geriatric research.
How it works
frailty index = criteria met ÷ 5 · Fried phenotype: 0 met = robust · 1–2 = pre-frail · 3–5 = frail (criteria: weight loss, exhaustion, weakness, slowness, low activity)
The Fried phenotype defines frailty by five measurable criteria — unintentional weight loss, self-reported exhaustion, weak grip, slow gait and low activity. Meeting three or more classifies someone as frail, one to two as pre-frail. The frailty index expresses the count as a 0–1 fraction of deficits, a format also used in larger deficit-accumulation indices. Frailty predicts falls, hospitalization and slower recovery, but the pre-frail stage frequently improves with strength training and better nutrition, which is why early screening is useful.
Worked example
An older adult who reports feeling exhausted and does little physical activity, but has no weight loss, normal grip and normal walking speed, meets 2 of 5 criteria — a frailty index of 0.40 and a "pre-frail" category that resistance exercise can often reverse.
Frequently asked questions
Is frailty the same as being old or disabled?
No. Frailty is a state of reduced reserve that makes small stresses have big effects. Many older adults are not frail, and frailty can occur alongside — but is distinct from — specific disabilities or diseases.
Can frailty be reversed?
Pre-frailty and mild frailty often improve. Progressive resistance exercise, enough protein (about 1.0–1.2 g/kg), treating underlying illness and reviewing medications are the mainstays.
How is the frailty index different from the phenotype?
The phenotype counts five specific criteria; a frailty index expresses deficits as a fraction of items assessed and can use dozens of variables. This tool uses the five Fried items and reports both the count and the fraction.
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Educational estimate only — not a medical diagnosis or a substitute for professional assessment. Screening scores and reference values are population tools; they cannot judge your individual health. Discuss any concerns with a doctor, nurse or pharmacist.