How is the payback time calculated?

The purchase price is divided by the yearly electricity saving. The saving is the difference between the two appliances in kWh per year, multiplied by your price per kWh.

Where do I find kWh per year or kWh per 100 cycles?

Both are printed on the appliance's energy label and repeated in the product database behind the label's QR code. Cooling appliances are stated per year, washing and drying appliances per 100 cycles.

What if the new appliance uses more energy?

Then there is no yearly saving and the calculator reports that the purchase is never repaid by electricity. Any reason to buy has to come from elsewhere: capacity, reliability, or features.

Should I include installation and delivery?

Add them to the purchase price if you want the full picture. The calculation treats the price field as everything you pay to get the new appliance running.

Does it account for rising electricity prices?

No. It holds your price per kWh constant. If you expect prices to rise, run the calculation again with a higher rate to see how much sooner the purchase repays itself.

Can I save or share the comparison?

Yes. Share copies a link that reopens the calculator with the same figures, and download or print keeps the inputs and results as plain text.

Appliance replacement calculator

Enter what your current fridge, freezer, washing machine, dishwasher, or tumble dryer uses, what the replacement uses, what it costs to buy, and your own price per kilowatt-hour. The calculator shows the yearly saving, how long the purchase takes to repay itself, and the total cost of each option over the years you choose.

Written by Kenneth Schrøder, Founder of WiseCalcs

Updated September 6, 2026·Sources verified September 6, 2026

A replacement pays for itself when the purchase price divided by the yearly electricity saving is shorter than the time you expect to keep the appliance — this calculator works out that number from the energy label figures you already have.

Saving per year

$54.00

Payback time: 13 years
Net gain over the period: -$160
Energy saved per year: 300 kWh
Total cost of keeping: $810
Total cost of replacing: $970

There is a saving, but the purchase price is not repaid inside the period you chose.

Keep ReplaceYear 0–10

The headline is the electricity you stop paying for each year. Payback time is the purchase price divided by that saving, and the chart shows cumulative cost for both options so you can see the year the lines cross and replacing becomes the cheaper path.

How does it work?

A label figure in kWh per 100 cycles is turned into a yearly figure first: label ÷ 100 × cycles per year. Payback ignores interest, repairs, and the resale or scrap value of the old appliance, and it assumes your electricity price stays the same.

Appliance replacement payback formula

t = \frac{\text{price}}{(E_{\text{old}} - E_{\text{new}})\times p}

E_old: Energy the current appliance uses per year, in kWh.
E_new: Energy the new appliance uses per year, in kWh.
p: Your electricity price per kWh.
price: Purchase price of the new appliance.
t: Payback time in years.

An old fridge-freezer using 450 kWh a year against a new one using 150 kWh saves 300 kWh, which is 90 a year at 0.30 per kWh. A 700 purchase price pays back in 7.8 years, so it first breaks even in year 8. Over 10 years, keeping costs 1,350 and replacing costs 1,150 — a net gain of 200.

Expert tips

Label figures come from a standard test programme; a household that runs hotter, fuller, or more often will use more than the label says.
An old appliance often uses more than its original label because of worn seals, dust, and a tired compressor, so measuring it gives a better answer than reading the old sticker.
The result answers a money question only. A breakdown risk, a leaking freezer, or a much quieter machine can justify replacing well before the payback year.

Method & sources

The calculator converts both appliances to kilowatt-hours per year — directly from a kWh/year label, or from a kWh/100 cycles label times your own cycles per year — prices that energy at the rate you enter, and divides the purchase price by the annual saving to get the payback time. It then adds up both options over the period you choose, so you can see the total cost of keeping and of replacing side by side.

Sources

Where this method comes from — use these references to understand the formula, assumptions, and limits.

European Product Registry for Energy Labelling (EPREL) — European Commission, verified 2026-09-06
Regulation (EU) 2017/1369 setting a framework for energy labelling — Publications Office of the European Union (EUR-Lex), verified 2026-09-06
ENERGY STAR certified products and efficiency data — U.S. Environmental Protection Agency, verified 2026-09-06

How we calculate

Both appliances are compared on the same basis: either kWh per year or kWh per 100 cycles scaled by your cycles per year.
The electricity price you enter stays the same for the whole comparison period.
Keeping the old appliance costs electricity only; replacing it costs the purchase price plus the new appliance's electricity.
Payback is a simple division of purchase price by annual saving; it does not discount future money.
Delivery, installation, repairs, and the resale or scrap value of the old appliance are not included unless you fold them into the purchase price.

Limitations

Label figures come from a standard test programme; a household that runs hotter, fuller, or more often will use more than the label says.
An old appliance often uses more than its original label because of worn seals, dust, and a tired compressor, so measuring it gives a better answer than reading the old sticker.
The result answers a money question only. A breakdown risk, a leaking freezer, or a much quieter machine can justify replacing well before the payback year.

Rounding

Money is rounded to two decimals for the annual saving and to whole units for the totals; payback is shown with one decimal and energy as whole kWh. The calculation itself uses full precision.

What this calculator does

Replacing a working appliance is a trade between a price you pay once and a saving that arrives in small monthly pieces. This calculator puts both on the same scale. It converts the old and the new appliance to kilowatt-hours per year, multiplies by the electricity price you actually pay, and compares the total cost of keeping what you have against buying the replacement and running it.

How to use it

Choose how the energy figures are written: kWh per year, or kWh per 100 cycles.
Enter the figure for the appliance you have now and for the one you are considering.
If you chose per 100 cycles, enter roughly how many cycles you run in a year.
Enter the purchase price of the new appliance and your price per kWh.
Set the comparison period — usually how long you expect to keep the new appliance.

Where the kWh figures come from

Cooling appliances are labelled in kWh per year, while washing machines, dishwashers, and tumble dryers are labelled in kWh per 100 cycles, because their energy use depends on how often you run them. Both are printed on the energy label and listed in the product database the label's QR code points to. For the appliance you already own, a plug-in energy meter left in place for a week gives a more honest number than a decade-old sticker.

A worked example

An old fridge-freezer uses 450 kWh a year and the replacement is rated at 150 kWh. That is 300 kWh saved, or 90 a year at 0.30 per kWh. A purchase price of 700 divided by 90 gives a payback of 7.8 years, so the first full year in the black is year 8. Over a 10-year comparison, keeping costs 1,350 in electricity and replacing costs 1,150 in total — a net gain of 200.

The same appliance measured per cycle

A tumble dryer labelled 235 kWh per 100 cycles run 160 times a year uses 376 kWh; a heat-pump model at 175 kWh per 100 cycles uses 280 kWh over the same 160 loads. The difference is 96 kWh a year, which is where the price per kWh and the purchase price decide the answer. Change the cycles per year and the payback moves with it — that is the point of entering your own laundry habit rather than a standard household.

What the payback figure leaves out

Interest or the return the purchase price would have earned elsewhere.
Delivery, installation, and taking the old appliance away, unless you add them to the price.
Whatever the old appliance would fetch second-hand, or a trade-in discount.
Repairs you avoid by replacing a machine that is close to failing.
Water use, which matters for washing machines and dishwashers but is not part of this calculation.

Common mistakes

Comparing a per-year figure with a per-100-cycles figure. Put both appliances on the same basis first.
Using the old label's kWh for an appliance that has been running for fifteen years; measure it if you can.
Entering only the energy part of the electricity price. Use the rate you actually pay per kWh, including the per-kWh taxes and tariffs on your bill.
Setting a comparison period longer than the appliance is likely to last.

When replacing makes sense anyway

If the payback lands beyond the period you set, the honest answer is that the electricity saving alone does not justify buying now — but a freezer that no longer holds temperature, a machine that has already needed one repair, or a kitchen renovation changes the decision. Use the number as the money half of the argument, and treat reliability and comfort as the other half.

FAQ

How is the payback time calculated?: The purchase price is divided by the yearly electricity saving. The saving is the difference between the two appliances in kWh per year, multiplied by your price per kWh.
Where do I find kWh per year or kWh per 100 cycles?: Both are printed on the appliance's energy label and repeated in the product database behind the label's QR code. Cooling appliances are stated per year, washing and drying appliances per 100 cycles.
What if the new appliance uses more energy?: Then there is no yearly saving and the calculator reports that the purchase is never repaid by electricity. Any reason to buy has to come from elsewhere: capacity, reliability, or features.
Should I include installation and delivery?: Add them to the purchase price if you want the full picture. The calculation treats the price field as everything you pay to get the new appliance running.
Does it account for rising electricity prices?: No. It holds your price per kWh constant. If you expect prices to rise, run the calculation again with a higher rate to see how much sooner the purchase repays itself.
Can I save or share the comparison?: Yes. Share copies a link that reopens the calculator with the same figures, and download or print keeps the inputs and results as plain text.