The model, stated exactly
Paper towels: 2 sheets per dry, at a roll price of $1.20 for 60 sheets, so each sheet costs $1.20 / 60 = $0.02 and each dry costs 2 × $0.02 = $0.04. Hand dryer: 1.8 kW × 25 seconds, so each dry uses 1.8 × 25 / 3,600 = 0.0125 kWh, which at $0.17 per kWh costs 0.0125 × $0.17 = $0.002125 per dry. The dryer purchase, $35 over 5 years, adds $35 / 5 = $7.00 a year. Annual totals use 365 days a year: at 8 uses a day that is 2,920 dries a year. Paper towels therefore cost 2,920 × $0.04 = $116.80 a year, and the dryer costs 2,920 × $0.002125 = $6.21 a year in electricity, plus $7.00, for $13.21 a year — a saving of $116.80 − $13.21 = $103.59 a year. The calculator rounds the electricity annual total to cents before adding the purchase cost, so the saving always equals the difference of the two rounded annual totals.
The worked example, line by line
Setup: 8 uses a day, 2 sheets per dry, a $1.20 roll of 60 sheets, a 1.8 kW dryer running 25 seconds, electricity at $0.17 per kWh, a $35 dryer lasting 5 years.
Line 1 — the sheet cost. $1.20 / 60 sheets = $0.02 per sheet.
Line 2 — paper per dry. 2 sheets × $0.02 = $0.04 per dry.
Line 3 — dryer energy per dry. 1.8 kW × 25 / 3,600 = 0.0125 kWh per dry.
Line 4 — dryer electricity per dry. 0.0125 kWh × $0.17 = $0.002125 per dry.
Line 5 — dries a year. 8 × 365 = 2,920 dries a year.
Line 6 — paper a year. 2,920 × $0.04 = $116.80 a year.
Line 7 — dryer a year. 2,920 × $0.002125 = $6.21 in electricity, plus $35 / 5 = $7.00 purchase cost, for $13.21 a year.
Line 8 — the saving. $116.80 − $13.21 = $103.59 a year saved by the dryer.
Try these
Quieter restroom: 4 uses a day. Paper towels fall to $58.40 a year (1,460 dries × $0.04), while the dryer falls to $10.10 a year ($3.10 in electricity plus the same $7.00 purchase cost) — a saving of $48.30 a year. Halving the traffic roughly halves the paper bill, but the dryer keeps its fixed $7.00 purchase cost, so its total falls by less.
Wasteful tearing: 3 sheets per dry. Paper towels jump to $175.20 a year (2,920 × $0.06), while the dryer stays at $13.21, so the saving grows to $161.99 a year. This is the branch that decides most real restrooms: people rarely use exactly two sheets, and every extra sheet is pure paper cost with no dryer equivalent.
Expensive electricity: $0.30 per kWh. Paper towels are unchanged at $116.80 a year, while the dryer rises to $17.95 a year ($10.95 in electricity plus $7.00), so the saving narrows to $98.85 a year. Even nearly doubling the electricity price barely dents the dryer advantage, because the dryer uses so little energy per dry.
Fast dryer: 15 seconds per dry. The dryer uses 1.8 × 15 / 3,600 = 0.0075 kWh per dry, costing $0.001275, so its annual total falls to $10.72 a year ($3.72 in electricity plus $7.00) against paper towels at $116.80 — a saving of $106.08 a year. Shorter drying also means shorter queues, which is a second, unpriced win in a busy restroom.
Output · formula · meaning
| Output | Formula | What it means |
|---|
| Paper cost per dry | Sheets × roll price / sheets per roll | $0.04 at the defaults — the number every other total hangs on. |
| Dryer energy per dry | Power (kW) × seconds / 3,600 | 0.0125 kWh at the defaults — tiny, which is why electricity is the smaller dryer cost. |
| Dryer electricity per dry | Energy per dry × price per kWh | $0.002125 at the defaults — about one-twentieth of the paper cost per dry. |
| Paper cost per year | Uses × 365 × paper per dry | $116.80 at the defaults — the bill that never stops. |
| Dryer cost per year | Uses × 365 × dryer per dry + purchase / life | $13.21 at the defaults ($6.21 electricity + $7.00 purchase). |
| Annual saving | Paper per year − dryer per year | $103.59 at the defaults — the dryer wins by nearly nine to one. |
Who uses this
- The office manager fitting out a restroom: enters the building's daily traffic and sees whether the dryer pays for itself in months — at 8 uses a day the $35 dryer is repaid by the $103.59 annual saving in about four months.
- The homeowner choosing a bathroom dryer: enters a realistic 4 uses a day and learns the dryer still saves $48.30 a year, even before counting the paper towels no longer bought, stored, and carried home.
- The cafe owner tired of the paper mountain: tries 3 sheets per dry — the honest figure for hurried customers — and finds the saving is $161.99 a year, plus a restroom that no longer overflows on busy days.
- The facilities lead writing the sustainability report: uses the same numbers to price the switch and to separate the energy story (tiny) from the waste story (large), instead of quoting a single vague saving.
Accuracy & limitations
The arithmetic is exact for the inputs you enter; the uncertainty is all in the inputs. Real sheet counts vary by person and by dispenser, and a restroom where people routinely pull four sheets will cost far more than the two-sheet default — which is why the calculator lets you change it. Real dryers vary too: a high-speed dryer may draw more power but run for fewer seconds, and a dryer that also heats the air uses more energy than the simple power-times-time model here. Installation, maintenance, and replacement filters or parts are not in the model, and neither is the cost of restocking, storing, and disposing of paper towels, which would widen the dryer advantage. Hygiene is deliberately outside this calculator's scope — studies disagree, drying quality matters as much as method, and no cost figure settles it — so treat this page as the money answer and judge hygiene separately. Error policy: empty, zero, or negative inputs, and inputs above their caps, are reported as errors rather than calculated, so no result ever rests on a nonsense input.
Cite this calculatorBright Side Kit. “Hand Dryer vs Paper Towels: Which Costs Less Per Year?.” brightoolbox.com, 2026.Bright Side Kit. "Hand Dryer vs Paper Towels: Which Costs Less Per Year?." https://brightoolbox.com/hand-dryer-vs-paper-towels/ Accessed October 24, 2026.
Embed this calculatorPaste this into any web page to embed the live calculator. The “Powered by Bright Side Kit” link below it must stay intact.