Disability Income Calculator
Calculate your monthly income gap and recommended disability-insurance cover if you can no longer work.
Why Disability Income Insurance Matters
Most people insure their life, their home, and their car — but not the engine that pays for all of them: their ability to earn an income. Disability is more common than most people think: the US Social Security Administration estimates that 24% of 20-year-old workers will become disabled before age 67, compared with 13% who will die. Despite this, disability insurance is the most under-bought protection product.
The three numbers that matter
- Monthly income gap — Your target replacement income (typically 60-70% of take-home pay) minus any existing benefits you already receive.
- Emergency-fund runway — How many months your existing savings can cover essential expenses while a claim is being processed (most policies have a 30-180 day waiting period).
- Lifetime gap to retirement — The total income you would lose if you were disabled today and could never return to work. This sets the upper-bound need.
How to buy disability cover smartly
Look for an own-occupation definition of disability rather than any-occupation — the former pays out if you can't do your specific job, while the latter only pays if you can't do any job at all. Choose a waiting period that matches your emergency fund (longer waiting period = cheaper premium). Stack a small individual policy on top of any group cover from your employer, because group cover usually ends when employment does.
Sources & assumptions
Checked on 10 October 2026.
- SSA Actuarial Note 2025.6 — an estimated 24% of 20-year-old US workers will become disabled before age 67, compared with 13% who will die.
- US Bureau of Labor Statistics: disability insurance plans — the median long-term disability plan replaces 60% of earnings; the median short-term plan lasts 26 weeks.
- Council for Disability Awareness (industry non-profit) — just under 1 in 4 of today’s 20-year-olds will be out of work for at least a year before retirement.
Our assumptions: the 70%-of-take-home default target is our choice. The lifetime gap simply multiplies the monthly gap by the years left to retirement, with no investment return or inflation adjustment.