PhySyCalc - Scientific and Engineering Calculator with Units

Struggling with your physics, chemistry, or engineering homework?

Can't get the answer in the right units?

Meet PhySyCalc

PhySyCalc is the only calculator on the app store with units. And we're not talking about a unit conversion app. PhySyCalc is a full blown scientific calculator that can add, subtract, multiply, divide, raise to powers, and do many other operations with numbers and units representing actual physical quantities.

Do you cook?

Shop at market? Then PhySyCalc is for you. Scale or convert your ingredient quantities in no time at all.

Science student or professional?

Then PhySyCalc is really designed for you. PhySyCalc has all the math functions you expect on a conventional calculator and more. Using just the element symbol, you can retrieve atomic weights, isotope weights, and isotope abundances.

Built into the calculator are many useful mathematical functions, as well as a number of useful physical constants. Included also are the speed of light, and the mass of the electron, proton, and neutron, all with appropriate units.

Get the right answer faster.

Remember this homework problem?

What pressure in atmospheres does 0.078 moles of hydrogen exert on the walls of a 42.0 mL container at 25.0 °C?

If you're clever you already know that you need to use the ideal gas equation of state, pV = nRT.

So, you identify the variables

n is the # of moles = 0.078 mol
T is the temperature in Kelvin = 273.15 K+25.0 K = 298.15 K
V is the volume = 42.0 mL
R is the gas constant = 8.314510 J/(K • mol)

and know that you can get the pressure using p = nRT/V. You pull out your calculator and plug in the numbers

0.078 • 8.314510 • 298.15 / 42.0 = 4.60380357635714

and write down 4.6 on the exam. Time to move on to the next problem, right? Not so fast: don't you need units on that number? Oh yeah, the question asked for the pressure in atmospheres. So, it's 4.6 atmospheres, right? Guess again! Maybe you should write out the calculation on paper with units:

0.078 mol • 8.314510 J/(K • mol) • 298.15 K / 42.0 mL

Rats! Now you have to do two calculations. Do the number calculation on the calculator (and get 4.6), and work out the final units calculation by hand on paper.

mol • J/(K • mol) • K / mL = J/(mol • mL)

OK, the answer is 4.6 J/(mol * mL). But wait, you need the answer in atmospheres! Gosh, this seems like a lot more work than it needs to be.

We agree!

With PhySyCalc you can enter the entire calulation with numbers and units and get the numerical answer with the correct units. Try it.

And there are all the possible answers with the correct units.

Wait! You need the answer in atmospheres. No problem. Simply scroll down, select the answer in atmospheres, and press done. It's that easy!

Throw away those tables

We've added fundamental physical constants so you no longer waste time looking them up. For example, instead of typing in the full gas constant with units you can just pull up the constants and keep on calculating. And the best part is that PhySyCalc gives you the right answer without worry the units of the gas constant (or any constant). Kiss all those dimensional analysis problems goodbye!

Other fundamental constants we've included are:

Constant Shortcut
π π
Gas Constant R
Avogadro Constant N_A
Planck Constant &h
Planck Constant/2 π &hbar
Boltzmann Constant k_B
Faraday Constant &F
speed of light c_0
Acceleration due to gravity (at sea level) g_0
electron charge q_e
electron mass m_e
proton mass m_p
neutron mass m_n
electric constant ε_0
magnetic constant µ_0
atomic weight aw[Element Symbol]
isotope weight aw[Isotope Symbol]
isotope abundance abundance[Isotope Symbol]
isotope nuclear spin spin[Isotope Symbol]
isotope nuclear gyromagnetic ratio γ_n[Isotope Symbol]


Atomic weights of any element or isotope in the periodic table are immediately available with an element symbol.

If you need the atomic weight of 16O isotope you can use


If you need the natural abundance of 10B use


PhySyCalc features include:

  • Quantity units supported in all calculations
  • Natural infix notation for entering calculations in full before evaluating
  • Intuitive interface for appending units unto numbers so you can enter your calculation quickly
  • Minimal buttons in portrait display for ease and speed of use
  • Complex number support
  • Press and hold delete button to clear entire display
  • Left swipe display for unlimited undo makes it easy to find mistakes and correct them
  • Right swipe display for redo
  • Swipe up for keyboard
  • Swipe down and navigate to the right unit for quantity
  • Swipe two fingers down on screen for full list of quantities and units
  • Double-touch slide on display to reduce the number of significant figures
  • Rotate to landscape for more units and scientific functions
  • Press and hold any math function to apply to entire display
  • Press and hold = button to retrieve value stored in memory
  • Saves and recalls results to memory
  • Universal app, supporting both iPhone and iPad displays

What are you waiting for? Buy it now at the AppStore