The best free calculator on the app store.
Oh yeah, it's ad-free too.

Available on the App Store
The Missing Calculator - Screenshot

Full Expressions

An advanced mathematical engine processes full expressions so you can do more than one thing at a time.

Full support for the standard order of operations.

Interactive History

Every time you perform a calculation, the result is saved. Tap any previous result to use it in your current calculation.


Format numbers with commas, spaces, or no separators.

Supports scientific notation. Even has smart-scientific mode.

Change number of decimal digits.

And More

  • Portrait and landscape support.
  • Color schemes to suit your taste.
  • Locale support.
  • Rounding indicator alerts you if answer has been rounded.
  • Optional button sounds.
Standard calculator screenshot

Standard Calculator

What's included:

An incredibly advanced calculator that supports full length expression entry, interactive history, number formatting, rounding indicator, decimal precision settings, and scientific notation.

What's the catch?

None, really. This is a free calculator without ads. Not now, not ever.

Scientific Calculator Add-On 099

Missing the scientific functions? Free for a limited time, the scientific calculator brings advanced math functions that extend the advanced mathematical engine and awesome UI. More specifically, you get:

  • Sine, Cosine, Tangent
  • Arc Sine, Arc Cosine, Arc Tangent
  • Natural Log
  • Common Log
  • Binary Log
  • Pi and Euler's
  • Square/Cube Shortcuts

To the mathematicians: Some functions (with button stripe) process numbers using floating-point values. As a result, these functions have the potential to be slightly inaccurate due to the restrictions inherent with floating-point math. This is negligible for most situations.

Programmer calculator screenshot

Programmer's Calculator Add-On 099

Want to take the two's complement of a number, rotate it left twice, and view it in hexadecimal? $0.99 gets you this (and a whole lot more).

  • Entry in binary, octal, decimal, and hexadecimal
  • Bit manipulation editor
  • Bit shifting
  • Bit rotating
  • Bitwise AND, NAND, OR, NOR, XOR, and XNOR
  • Two's complement and one's complement
  • Signed or unsigned decimal modes
  • 64, 32, 16, and 8 bit math

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Meet The Developer

Evan Edstrom Picture

Evan Edstrom

Evan is the owner of Edstrom Technologies and has worked as a software engineer for two of the world's leading technology companies. He has worked professionally on high-level database systems, data mining applications, industrial control systems, quality assurance framework tools, and embedded hardware systems. He took up programming at age seven and soldering at age nine. Evan is working towards a bachelors degree in computer science at Whitworth University in Spokane, Washington.