Calchemy - Units Calculator app for iPhone and iPad

Finally, a revolutionary new calculator that “understands” units of measure! Calchemy is the combination of a units conversion engine and a scientific calculator that greatly simplifies real-world problem solving.

With Calchemy you get the answers to your real-world calculations in the units you want, without ever having to look up or enter a conversion factor. Just enter the numbers into a calculation along with their units of measure, Calchemy does all the necessary unit conversions for you automatically when it solves the equation. It also makes sure sure your equation is dimensionally correct.

Calchemy makes getting correct results so simple, you might find yourself calculating just for fun!

One of the most frustrating elements of real-world calculations is that units conversions are often required to get the data you have into a form that is compatible with a known physical relationship. This is a result of the widespread use of so-called "practical units" that are prevalent in almost every field of technology. With Calchemy the units are carried through calculations with conversions applied as required to deliver the answer in the units you specify. In fact, quite remarkably, in many cases a math-magical technique built into Calchemy called "Solve By Dimensional Analysis" can even derive the algebraic equation relating the parameters for you!

Calchemy is great for solving problems that deal with energy, renewable resources, power, pressure, volume, area, force, speed, distance etc. Calchemy “understands” hundreds of units of measure and many physical properties, so you can focus on the problem and not be distracted by conversions. From basic unit conversions, to complex calculations, Calchemy does them in "one line"!

Take a look at the examples below and then give Calchemy a try for yourself, you wont be disappointed, real-world problem solving has never been so easy!


What is 10 kilometers per liter in miles per gallon?

10 km/l ? mpg
= 23.5215 mpg


What is the length of the sides of a square 3 acre garden?

sqrt(3acres) ? ft
= 361.497 ft


How much power does it take to deliver compressed air at 5 cubic feet per second and 200 psi?

200 psi ; 5cfs ? hp
= 261.919 hp


What is the radius of a balloon that holds one gallon of water?

( 3 / (4 pi) * 1 gal )^(1/3) ? inches
= 3.80634 inches


How long should I leave my lawn sprinkler running?

(50 ft * 30 ft * 0.75 inches/week) / (5 gal/min) ? hours/week
= 2.33766 hours/week


How long will it take to get hot water from a water heater to the faucet through 160 ft of half inch (id) tubing with a flow rate of 5 gallons per minute?

pi * (0.25 inch)^2 ; 160 ft ; 5 gal/min ? sec
= 19.5839 sec


How long will it take for my hot water heater to fully recover after the shower goes cold?

40 gal ; 120 degF – 45 degF ; hsv_water ; 40000 btu/hr ? min
= 37.5542 min


What is the equivalent “charging power” when I fill up the gas tank on my car (in 2 min and 20 seconds)?

20 gal ; 2 min + 20 sec ; hcv_gasoline ? megawatts
= 17.4872 megawatts

OK, last one, using Calchemy (and statistics from the web), I calculate that at the current rate of world fossil fuel consumption the volume of CO2 gas added to the atmosphere each year is a layer one half inch thick covering the whole earth (at sea level). So after 120 years of consumption it would be up to my nose... Um, how long have we been burning fossil fuels?

Have FUN calculating!