Price an Appliance From Its Own Duty Cycle — Free, Before You Replace It
Every sticker wattage is a maximum, and the annual cost of an appliance is decided by the hours it really runs at that draw. A fridge cycling twenty minutes an hour and a heater running flat out all winter are impossible to compare from the label alone.
The proof surface
Free path: the tool computes locally in this browser with no key and no account. Where an AI step helps, any free chat assistant works — free tiers exist (Google AI Studio, Groq), but plans and limits change, so check the provider's own page. No third-party service is claimed here as verified: UNCONFIRMED — model has no browsing access this session.
Why the flat version breaks
The energy label gives a category and a yearly estimate for a standard household, which is close to useless when your usage is not standard. Entering the watts, your own run-time and the rate on your last bill prices the unit you actually own, and adding the replacement wattage turns it into a replacement decision.
How to use the appliance running-cost strip in four passes
A plug meter costs less than a month of the wrong assumption. If you cannot measure it, use the rated watts and treat the result as an upper bound — the strip says which figure it used.
Cycling appliances are where estimates go wrong: a fridge runs roughly a third of the time it is powered. Watch it for one cycle and multiply, or check whether the manual gives a duty cycle.
Standing charges are excluded and time-of-use bands are averaged by the number, so the annual figure is an estimate for the hours you entered. Re-run it after a tariff change — the number moves more than people expect.
The replacement line uses identical hours and rate, so the difference is the appliance and nothing else. Divide the purchase price by the annual saving to get months to payback, and compare that with the warranty.
SAMPLE DATA, NOT A VERIFIED CLAIM: the starter record is a garage chest freezer drawing 145 watts for nine hours a day on a 31-cent tariff. Replace these values with your own source before you rely on anything.
What breaks first
Using the energy label's annual figure as your own
Labels assume a standard household, a standard tariff and standard usage. If your garage is cold or your family does four loads a week, the label is somebody else's year, not yours.
Comparing a heat pump dryer with a vented one on watts alone
A heat pump dryer runs longer at lower watts and often comes out cheaper overall, which is exactly what this strip shows when the hours are entered honestly. Watts alone would rank it wrong.
Replacing a working appliance on a two-year payback
Payback competes with the risk of a new unit failing outside warranty and the embodied cost of scrapping a working one. Use the number as one input, not as a verdict.
What you pay otherwise
| The usual route | What it leaves out | Cost |
|---|---|---|
| Smart-plug app subscription | Monthly fee for a graph of the same arithmetic you can do once | $3–$8 a month |
| A plug meter | One-off cost, pays for itself the first time it corrects a duty-cycle guess | $15–$30 once |
| Replacing on the label estimate | Buying a rated-watts improvement that never shows up on the bill | the purchase price |
| This page + the free appliance running-cost strip | Computed in your tab, result on screen before you type anything | $0 |
Try the free appliance running-cost strip right here
Load the starter freezer and change the hours to 24 to see how far a duty-cycle guess moves the annual figure.
FIRST-LOAD · sample record filed
Take it into the free appliance running-cost strip
The companion app runs the same logic with a numbered intake, three starter records, a stateful share link, the one-time printable layer, and the local history shelf.
Open the free appliance running-cost strip →Keep the work if you will use it again
The full strip: daily, monthly and annual draw, the annual cost, the replacement comparison and the payback, unlimited re-runs.
The on-screen result is free and complete. The one-time layer adds a tangible file you keep and the saved history that comes with it.
Boundary: This estimates running cost from figures you enter; it is not a metered measurement, it does not predict tariffs, and it excludes standing charges, time-of-use bands and maintenance. Use your own bill for the rate and treat the annual figure as an estimate.