Air-Conditioner BTU Sizing from Room Size Calculator
Estimate the cooling capacity (BTU/h) needed for a room from its area, ceiling height (relative to 8 ft baseline) and nu...
Tipping, cooking, travel, and other useful little tools.
The calculators that come up in day-to-day life — tip splitting, cooking conversions, fuel costs, and trip planning.
Estimate the cooling capacity (BTU/h) needed for a room from its area, ceiling height (relative to 8 ft baseline) and nu...
Compute the carpet (and padding) needed to cover a rectangular room, in square yards, with a chosen waste allowance for...
Estimate days between watering for a potted houseplant from the pot diameter (larger pots dry out more slowly) and the s...
Estimate the daily caloric needs (DER, daily energy requirement) for a dog or cat: resting energy requirement RER = 70 ·...
Compute the cubic yards of gravel needed to cover a driveway of given length, width, and depth, with an optional waste/c...
Compute the number of dump-truck loads needed to haul a given volume of soil, given the truck capacity in cubic yards. S...
Compute the cost to refill a propane tank from its current level to a target fill level (typically 80 % for safety), giv...
Compute the number of standard 3-tab asphalt shingle bundles needed for a sloped roof, given roof area, a waste allowanc...
Compute the recommended tongue weight (downward force on the hitch ball) for a conventional ball-coupler trailer: 10-15...
Estimate the total cost and per-guest cost of a party, given fixed costs (venue, decor) and per-guest costs (food, drink...
Estimate trip fuel cost from distance, fuel economy, and price per unit.
Compute the number of rolls of synthetic roofing underlayment needed for a roof, including 10 % overlap and waste, given...
Compute the number of wall studs required for a straight wall of given length and on-centre spacing, plus extras for doo...
Find the day of the week for any past or future date, plus the day-of-year, ISO week number, and how far the date is fro...
Estimate the loaded-salary cost of a meeting from the number of attendees, their average hourly rate, and the meeting le...
Compute the number of ceiling joists required to span a rectangular ceiling, given the span direction (joists run perpen...
Estimate a tree's age from its trunk circumference at chest height and a species-specific annual growth factor.
Compute the number of pavers needed to cover a rectangular patio or walkway from the area to be paved and the dimensions...
Compute typing speed in words per minute (WPM) from total words typed and the time taken, with adjustment for accuracy.
Compute the linear feet of crown molding needed for a rectangular room (perimeter), the number of standard 12-foot stick...
Compute the sale price and amount saved when an item is marked down by a percent discount.
Estimate the total fuel cost of a road trip and the per-person share, given total distance, fuel economy, fuel price, an...
Count the number of business days (Monday–Friday, inclusive) between two dates, with the option to subtract a manual cou...
Compute the unit price of two pack sizes (price ÷ quantity) so you can quickly identify which is the better deal.