Disability Insurance Need Calculator
Disability insurance replaces part of your income if illness or injury stops you working, and sizing it starts with a simple question: how much of your monthly pay would you need to keep the household running? This calculator multiplies your gross monthly income by a replacement percentage you choose, then subtracts any benefit you already receive from an employer or government program to show the additional monthly benefit you may need to insure. Private policies commonly replace around 60 percent of gross income, partly because individually paid benefits are often received tax-free, which narrows the gap to your take-home pay and helps keep fixed bills covered. Enter your monthly income, the percentage you want to protect, and any existing cover so the result reflects the true shortfall you would face. Because policy definitions of disability, waiting periods and benefit lengths vary widely, this is a planning estimate, not a quote; read any policy's own and occupation clauses carefully. Use it to gauge whether your current protection is adequate before you shop for a new policy or adjust an existing one. Every figure is computed deterministically from the formula shown below, with a worked example that reconciles exactly to the calculator defaults.
The need is monthly income x replacement percent, less existing benefit. Replacing 60% of a 6,000 monthly income with no existing cover gives a needed monthly benefit of $3,600.00.
Disability insurance need formula
Target benefit = monthly income x replacement percent
Additional need = target benefit - existing benefit
Replacement percent is entered as a number, e.g. 60
The additional need is floored at zero, so if existing cover already meets the target the formula returns no further need rather than a negative figure.
Worked example
Suppose your monthly income is 6,000 dollars, you want to replace 60 percent, and you have no existing cover.
- Convert the percentage: 60% = 0.60
- Target benefit: 6,000 x 0.60 = 3,600.00
- Existing benefit: 0.00
- Additional need: 3,600.00 - 0.00 = 3,600.00
The target monthly benefit is 3,600.00 dollars and, with no existing cover, the additional benefit needed is 3,600.00 dollars. These are the calculator's default inputs, so the result matches the widget exactly.
Disability Insurance Need Calculator: frequently asked questions
What percentage of income should disability cover replace?
Private long-term disability policies commonly replace about 60 percent of gross income. Because benefits paid from premiums you funded with after-tax dollars are usually received tax-free, 60 percent of gross can come close to your normal take-home pay. The right figure depends on your fixed expenses and other income.
Does Social Security count as cover?
Social Security Disability Insurance can provide a benefit if you have a qualifying disability and enough work credits, but its definition of disability is strict and approval can take time. If you expect to rely on it, enter an estimate as existing cover; the Social Security Administration publishes how its benefit is calculated.
What is an elimination period?
The elimination period, or waiting period, is the time between becoming disabled and when benefits begin, often 30 to 180 days. A longer waiting period lowers the premium but means you must cover that gap from savings. This calculator sizes the benefit amount, not the waiting period.
What does own occupation mean?
An own-occupation policy pays if you cannot perform your specific job, even if you could work in another role. An any-occupation policy pays only if you cannot work in any suitable job. Own-occupation cover is broader and usually costs more; read the definition before buying.
Should I include employer cover?
Yes. Many employers provide group short-term or long-term disability benefits. Enter the monthly amount as existing cover so the result shows only the additional benefit you need to buy individually, avoiding over-insurance.
Official sources
- Disability benefits and income replacement guidance: US Social Security Administration (SSA). As at 25 June 2026.
Reviewed by the CalculatorHub team, edited by James Graham, 25 June 2026. See our methodology. This is general information, not financial, tax, legal or investment advice.