Basic Calculator Online

eCalc is a free and easy-to-use online calculator that supports basic features. This calculator offers a negative sign, square root button, division, multiplications, addition, subtraction, EE function, and more.

Addition
Subtraction
Multiplication
Division
Sign
Square
Square Root
Inverse
Exponent
Percent
Memory Functions

Addition

The addition (sum function) is used by clicking on the "+" button or using the keyboard. The function results in a+b.

Subtraction

The subtraction (minus function) is used by clicking on the "-" button or using the keyboard. The function results in a-b.

Multiplication

The subtraction (minus function) is used by clicking on the "-" button or using the keyboard. The function results in a-b.

Division

The division (divide function) is used by clicking on the "/" button or using the keyboard "/" key. The function results in a/b.

Sign

The sign key (negative key) is used by clicking on the "(-)" button or using the keyboard "m"key. The function results in -1*x.

Square

The square function is used by clicking on the "x^2" button or using the keyboard shortcut "s". The function results in x*x

Square Root

The square root function is used by clicking on the "x" button or using the keyboard shortcut "r". This function represents x^.5 where the result squared is equal to x.

Inverse

Multiplicative Inverse (reciprocal function) is used by pressing the "1/x" button or using the keyboard shortcut "i". This function is the same as x^-1 or dividing 1 by the number.

Exponent

Numbers with exponents of 10 are displayed with an "e", for example 4.5e+100 or 4.5e-100. This function represents 10^x. Numbers are automatically displayed in the format when the number is too large or too small for the display. To enter a number in this format use the exponent key "EE". To do this enter the mantissa (the non exponent part) then press "EE" or use the keyboard shortcut key "e" and then enter the exponent.

Percent

The percent function is used by clicking on the "%" or using the keyboard. The percent function is used to add, subtract, multiply, or divide a percent of a number. It's used to calculate the percent of a number. Here are some examples:

73+4.5% = 76.285.

18/80% = 1.25.

Memory Functions

The memory functions allows you to store and recall calculations using a temporary stack storage element.

1. The memory plus function is used by clicking on the "M+" button. This adds the value to whatever is stored in memory (initially this value is zero).
2. The memory minus function is used by clicking on the "M-" button. This subtracts the value from whatever is currently stored in memory.
3. The memory recall function is used by clicking on the "MR" button. This recalls the value from the memory and places it into the working area. The value is still kept in memory.
4. To clear the memory value, click on the "clear" button twice.