My calculator contains several clickable elements containing number 0 to 9, also 4 primary mathematical operators; as "add, subtract, multiply and divide". Do not forget "decimal", which is important.
At any time, pressing the "clear" button clears the input and output values, and returns the calculator to its initialized state; 0 shown in output .

Any operation (+, -, *, /) performs well on numbers containing decimal points. The result has 3 decimal places of precision when it comes to rounding.