Appliance Life Expectancy Calculator

This calculator estimates the remaining useful life of a household appliance and weighs a repair quote against the cost of a new one, so you can decide whether to fix it or replace it.

The primary formula is the 50% Rule, scaled by age:

Replace if: Repair Cost ≥ 0.50 × (1 − Age Factor) × Replacement Cost

Where the Age Factor scales from 0 (brand new) to 1.0 (at the end of expected life):

Age Factor = Current Age / Expected Lifespan

Read the rule this way. A brand-new appliance justifies a repair costing up to half the price of a new one, because you get the full remaining life for that money. The allowance shrinks as the appliance ages, and hits zero once it reaches its expected lifespan, where any repair is buying time you cannot count on.

Watch the direction. If you see the rule written without the (1 − Age Factor) term, it says the older the appliance the more you should be willing to spend on it, which is backwards.

A secondary metric is Cost Per Year of Remaining Life:

CPY = Repair Cost / (Expected Lifespan − Current Age)

If CPY is close to what a new unit costs per year of its life, replacement is usually the smarter call.

Worked Example: Your washing machine is 9 years old. Washers run 10 to 14 years, so the midpoint the age factor uses is 12 years. Replacement cost is $700. A repair quote is $280.

• Age Factor = 9 / 12 = 0.75, so 25% of its life is left
• Repair allowance = 0.50 × 0.25 × $700 = $87.50
• $280 is more than three times that, so replace.
• CPY = $280 / (12 − 9) = $93/year, against about $58/year for a new $700 machine over 12 years. You would be paying more per year for the old one.

Average Appliance Lifespans: Refrigerator 13–17 yr; Washing machine 10–14 yr; Dryer 10–13 yr; Dishwasher 9–12 yr; Oven or range 13–15 yr; Microwave 9–10 yr; Water heater 8–12 yr; Garbage disposal 8–12 yr; Furnace 15–20 yr; HVAC (Heating, Ventilation and Air Conditioning) system 15–25 yr.

Factor in efficiency as well as age. A new Energy Star appliance typically saves $50 to $150 a year in running costs, which tips a borderline call further toward replacing. The saving is largest on the things that run constantly, so it matters much more on a fridge or a water heater than on a microwave.