Cost-Per-Use Calculator
Cost per use is the price of an item, plus what it costs to keep it running, minus what you can resell it for, divided by the number of times you actually use it. Enter your own numbers below to see the cost per use and cost per year, then add a cheaper option to find the break-even point: the moment buying once well becomes cheaper than buying twice.
Your item
Compare a cheaper option (optional)
The starting values are example defaults: $24.90 is the price shown on Amazon US for the Lodge 10.25-inch skillet on 2026-10-22; the 10-year lifespan, 3 uses a week and the $15 / 2-year cheaper pan are assumptions for illustration, not measurements. Replace them with your own.
Load a worked example:
Each example uses the price shown on Amazon US on the date stated; lifespans and uses are labeled assumptions.
Results
Enable JavaScript to use the calculator. Formula: (price + yearly upkeep × years − resale) ÷ (uses per week × 52 × years).
How the calculator works
The math is three lines, and you can check every one. Total uses = uses per week × 52 × years. Total cost of ownership = price + (upkeep per year × years) − resale value. Cost per use = total cost ÷ total uses; cost per year = total cost ÷ years.
Break-even compares running totals, not sticker prices. The cheaper option is bought again each time its lifespan runs out (one purchase per lifespan, rounded up). The durable item's running total is its price plus upkeep to date. Stepping month by month for up to 50 years, the calculator reports the first month the durable item's total is at or below the cheaper option's. Resale is left out of break-even because you only collect it when you sell.
What it does not model: inflation, financing, the time spent shopping for replacements, or whether the cheaper item fails early. Upkeep is treated as an even yearly amount. A warranty term is not a lifespan: a 1-year warranty doesn't mean a grinder dies at 13 months, and a lifetime warranty doesn't promise forever. Where a guide quotes a warranty, read it as the maker's promise, not our forecast.
Worked examples from our guides
Each example uses the price shown on Amazon US on 2026-10-22. The lifespan and weekly uses are assumptions you can change.
- Lodge 10.25-inch cast iron skillet, $24.90: at 3 uses a week for an assumed 10 years (1,560 uses), about $0.016 per use. See our Lodge cast iron skillet buy-once guide.
- Baratza Encore grinder, $149.95: daily use for an assumed 7 years (2,548 uses) is about $0.059 per use. The listing states a 1-year warranty, so the 7 years is an assumption, not a promise. See our Baratza Encore coffee grinder guide.
- Manduka PRO yoga mat, $144.00: 3 sessions a week for an assumed 10 years (1,560 uses) is about $0.092 per use.
For six more products worked through the same way, read Cost per use: what durable gear really costs over its life, and for gift ideas that hold up, see the Black Friday buy-it-for-life gift guide.
FAQ
How do you calculate cost per use?
Add the purchase price and any upkeep over the years you keep the item, subtract what you could resell it for, then divide by the number of times you use it. Uses = uses per week × 52 × years.
What is a break-even point in a buy-once comparison?
It is the moment the durable item's running total (price plus upkeep) drops to or below what you would have spent buying and re-buying the cheaper option. The calculator steps month by month for up to 50 years to find it.
Where do the example lifespans come from?
They are example assumptions you should replace with your own. A warranty term is not a lifespan, so we show the warranty the listing states next to each example instead of presenting a lifespan as fact.
Does the calculator include running costs like filters or electricity?
Only if you add them. Put any yearly repair, maintenance or consumable cost in the upkeep field and it is multiplied by the years you keep the item.
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