Buy vs Rent Tools: Break-Even Days Calculator 2026

Buy or rent that tool? Compare the totals, not the sticker prices

The sticker price is a trap: a $400 tool looks expensive next to a $45-a-day rental — until you count the days. Renting costs $45 every time you use it, and buying costs $400 once, plus a little maintenance, less whatever you sell it for. The honest comparison is the total cost of each side over the years you will use it: buy total = purchase price + annual maintenance × years − resale value; rent total = rental rate × days a year × years; difference = rent total − buy total (> 0 means BUY wins; < 0 means RENT wins; 0 is a tie). Cost per use (buy) = buy total / (days a year × years); cost per use (rent) = the rental rate. On the defaults — a $400 tool, $45 a day to rent, 6 days a year, 5 years, $20 a year in maintenance, $100 resale — the buy total is $400 + $20 × 5 − $100 = $400.00, the rent total is $45 × 6 × 5 = $1,350.00, and BUY wins by $950.00. The cost per use is $13.33 to own against $45.00 to rent. The break-even days per year — how many days a year you would have to use the tool for buying to win — are ($400 + $20 × 5 − $100) / ($45 × 5) = 1.78 days/yr (exact 1.7778). The break-even rental rate is $13.33/day (exact 13.3333). The break-even purchase price is $1,350.00. The break-even years are 1.2. The break-even maintenance is $210.00/yr. And there is NO resale break-even: the resale value that would tie the two is −$850.00, so buying wins even with a $0 resale value.

At the defaults — purchase price $400, rental rate $45/day, 6 days a year, 5 years, maintenance $20/yr, resale $100 — the buy total is $400.00, the rent total is $1,350.00, the difference is $950.00 in buying’s favour, and the winner is BUY wins. The cost per use is $13.33 to own against $45.00 to rent. The break-evens are: days per year 1.78 (exact 1.7778), rental rate $13.33/day (exact 13.3333), purchase price $1,350.00, years 1.2, maintenance $210.00/yr. Check the identities: buy = purchase price + maintenance × years − resale; rent = rental rate × days × years; difference = rent − buy; break-even days = buy total / (rental rate × years); break-even rental rate = buy total / (days × years); break-even purchase price = rental rate × days × years − maintenance × years + resale; break-even years = (purchase price − resale) / (rental rate × days − maintenance); break-even maintenance = (rental rate × days × years − purchase price + resale) / years. The winner is decided from the ROUNDED (to-the-cent) buy vs rent totals: equal rounded values are a tie. When the rental rate times the days is at or below the maintenance, there is NO break-even in years: the tool never pays for itself, and the page shows “—” with that explanation, not a number. Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum.

The worked example, line by line

Setup: purchase price $400, rental rate $45/day, 6 days a year, 5 years, maintenance $20/yr, resale $100.

Line 1 — the buy total. $400 + $20 × 5 − $100 = $400.00.

Line 2 — the rent total. $45 × 6 × 5 = $1,350.00.

Line 3 — the difference and the winner. $1,350.00 − $400.00 = $950.00; positive, so BUY wins.

Line 4 — the cost per use. $400.00 / (6 × 5) = $13.33 to own, against $45.00 to rent.

Line 5 — the break-even days. $400.00 / ($45 × 5) = 1.78 days/yr (exact 1.7778). Use the tool twice a year and buying wins.

Line 6 — the break-even rental rate. $400.00 / (6 × 5) = $13.33/day (exact 13.3333). Rent below $13.33 a day and renting wins.

Line 7 — the break-even purchase price. $45 × 6 × 5 − $20 × 5 + $100 = $1,350.00. A tool dearer than $1,350 loses to renting.

Line 8 — the break-even years. ($400 − $100) / ($45 × 6 − $20) = 1.2 years. After 1.2 years of ownership, buying is cheaper.

Line 9 — the break-even maintenance. ($45 × 6 × 5 − $400 + $100) / 5 = $210.00/yr. Maintenance above $210 a year would make renting win.

Reverse: the break-even days per year are 1.78 days/yr (exact 1.7778); at 1.78 days/yr the rent is $400.50 (BUY wins by $0.50), at 1.77 days/yr it is $398.25 (RENT wins by $1.75) — 1.78 is the nearest. The break-even rental rate is $13.33/day (exact 13.3333); at $13.33/day the rent is $399.90 (RENT wins by $0.10), at $13.34/day it is $400.20 (BUY wins by $0.20) — $13.33 is the nearest. The break-even purchase price is $1,350.00; a $1,350 tool costs $1,350.00 to buy, exactly tying the rent total. The break-even years are 1.2; at 1.2 years the buy total is $324.00 and the rent total is $324.00 — an exact tie. The break-even maintenance is $210.00/yr; at $210/yr maintenance the buy total is $1,350.00, tying the rent total. There is NO break-even resale value: the resale value that would tie is −$850.00, so buying wins even with a $0 resale value.

Every branch, checked

Purchase price $200: buy $200.00, rent $1,350.00 — BUY wins by $1,150.00. A cheaper tool only widens the gap.

Purchase price $800: buy $800.00, rent $1,350.00 — BUY wins by $550.00. Double the price and buying still wins by $550.

Purchase price $1,500: buy $1,500.00, rent $1,350.00 — RENT wins by $150.00 (FLIP). Past the $1,350 break-even price, renting wins — the first flip.

Rental rate $25/day: buy $400.00, rent $750.00 — BUY wins by $350.00. Cheaper renting narrows the gap but does not close it — $25 is still above the $13.33 break-even rate.

Rental rate $75/day: buy $400.00, rent $2,250.00 — BUY wins by $1,850.00. Dear renting makes buying a bargain.

Rental rate $10/day: buy $400.00, rent $300.00 — RENT wins by $100.00 (FLIP). Below the $13.33 break-even rate, renting wins.

2 days a year: buy $400.00, rent $450.00 — BUY wins by $50.00. Two days a year is just past the 1.78-day break-even, so buying wins by a whisker.

12 days a year: buy $400.00, rent $2,700.00 — BUY wins by $2,300.00. Use it every month and buying wins by a mile.

1 day a year: buy $400.00, rent $225.00 — RENT wins by $175.00 (FLIP). Once a year is below the 1.78-day break-even, so renting wins.

2 years owned: buy $340.00, rent $540.00 — BUY wins by $200.00. Two years is past the 1.2-year break-even, so buying wins.

10 years owned: buy $500.00, rent $2,700.00 — BUY wins by $2,200.00. Ten years of renting is $2,700 against $500 to own.

1 year owned: buy $320.00, rent $270.00 — RENT wins by $50.00 (FLIP). One year is below the 1.2-year break-even, so renting wins.

Maintenance $0/yr: buy $300.00, rent $1,350.00 — BUY wins by $1,050.00. No maintenance at all and buying wins by even more.

Maintenance $60/yr: buy $600.00, rent $1,350.00 — BUY wins by $750.00. Three times the maintenance and buying still wins — $60 is far below the $210 break-even.

Resale value $0: buy $500.00, rent $1,350.00 — BUY wins by $850.00. Even worth nothing at the end, the tool is worth buying.

Resale value $250: buy $250.00, rent $1,350.00 — BUY wins by $1,100.00. A better resale only widens the gap.

Reverse — the other way round: the break-even days per year are 1.78 days/yr (exact 1.7778); the break-even rental rate is $13.33/day (exact 13.3333); the break-even purchase price is $1,350.00; the break-even years are 1.2; the break-even maintenance is $210.00/yr; there is NO break-even resale value (the resale that would tie is −$850.00).

What the defaults assume

The model assumes you use the tool the same number of days every year, the rental rate and the maintenance stay the same, and the resale value is what you get at the end — it does not model the time value of money, the cost of storing the tool, or the trips to the rental shop. It assumes the tool lasts the whole ownership period with only the maintenance you enter. It leaves out delivery charges on rentals, the deposit, and what happens if the tool breaks: a broken $400 tool costs $400 to replace, and a broken rental costs nothing. With 0 days a year, the rent is $0.00 and RENT wins by $400.00 — a tool you never use is cheapest rented, which is to say not rented at all. With a $0 rental rate, the rent is $0.00 and RENT wins by $400.00 — free renting always wins. Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum; the reverses are nearest-value solutions, and the exact unrounded figures (1.7778, 13.3333, 1.2) are stated wherever the rounded figures appear.

Output · formula · meaning

Who uses this

• The homeowner eyeing a $400 pressure washer: they learn buying wins by $950.00 at 6 days a year for 5 years — so they know the washer pays for itself, and they check the 1-day-a-year branch (RENT wins by $175.00) before buying a tool they will use once.
• The renter comparing a $10-a-day deal: they learn below $13.33/day renting wins — so they know a $10-a-day rental is the better deal, and they check the $25-a-day branch (BUY wins by $350.00) before assuming every cheap rental wins.
• The buyer of a $1,500 table saw: they learn past the $1,350.00 break-even price renting wins by $150.00 — so they know the dear tool is the one to rent, and they check the $800 branch (BUY wins by $550.00) before renting every tool by default.
• The owner who keeps tools for a decade: they learn at 10 years buying wins by $2,200.00 — so they know long ownership is where buying pays, and they check the 1-year branch (RENT wins by $50.00) before buying a tool for a single job.

Accuracy & limitations

The math is exact for the numbers you enter: buy = purchase price + maintenance × years − resale; rent = rental rate × days × years; difference = rent − buy; break-even days = buy total / (rental rate × years); break-even rental rate = buy total / (days × years); break-even purchase price = rental rate × days × years − maintenance × years + resale; break-even years = (purchase price − resale) / (rental rate × days − maintenance); break-even maintenance = (rental rate × days × years − purchase price + resale) / years. The winner is decided from the ROUNDED (to-the-cent) buy vs rent totals: equal rounded values are a tie. What the model cannot do is know how often you will really use the tool: check the days, because the answer flips at 1.78 days a year — at 1 day renting wins by $175.00, at 2 days buying wins by $50.00. It assumes the same days every year, the same rental rate and maintenance, and the resale value you enter. It leaves out the time value of money, storage, delivery charges, and the cost of a breakdown. It is a cost comparison, not a buying guide: for whether to rent or buy a home, see the rent vs buy calculator; for whether to buy a 3D printer or outsource the printing, see the 3D printer buy vs outsource calculator.