Circles Calculator

This calculator focuses on the calculation of area, circumference, radius and diameter of a circle.

 

A = Area.

C = Circumference

R = Radius

D = Diameter

Example:

1 Calculate the area of a 10" circle.

key in 10, press A(D)

The answer is 78.54.

2. Calculate the Diameter of 78.54 sq. in. circle.

press "shift", D(A).

The answer is 10.

 

For more information:

Wikipedia Circle

Using the "long press" gesture will display a hint about any key. (Video: Displaying a hint) You can inspect the Key Details to see the formulas and functions for any key.

 

Label	Description
A(R)	Calculates the area of a circle given the radius.
A(D)	Calculates the area of a circle given the diameter.
A(C)	Calculates the area of a circle given the circumference.
C(R)	Calculates the circumference of a circle given the radius.
C(D)	Calculates the circumference of a circle given the diameter.
√	Calculates the square root of x.
x²	Calculates x squared.
1/x	Calculates the reciprocal of x.
SWAP	Swaps the x and y registers.
÷	Divides y by x.
ROLL	Rolls the stack down.
×	Multiplies y times x.
−	Subtracts x from y.
%	Calculates the x percent of y.
+	Adds y to x.

 

Label	Description
R(A)	Calculates the radius of a circle given the area.
D(A)	Calculates the diameter of a circle given the area.
C(A)	Calculates the circumference of a circle given the area.
R(C)	Calculates the radius of a circle given the circumference.
D(C)	Calculates the diameter of a circle given the circumference.
ln	Calculates the natural logarithm of x.
exp	Calculates the base-e exponential of x.
y^x	Calculates y raised to power of x.
%T	Calculates what percentage x is of y.
last x	Recalls the 'last x' value.
clr m	Clears all of the user memory.
clr s	Clears the stack registers (x, y, z, t).
π	Enters pi into x.
sin	Calculates the sine of x for the current degree/radian mode.
cos	Calculates the cosine of x for the current degree/radian mode.
tan	Calculates the tangent of x for the current degree/radian mode.
rand	Calculates a random number greater than or equal to 0 and less than 1.
asin	Calculates the arc sine of x for the current degree/radian mode.
acos	Calculates the arc cosine of x for the current degree/radian mode.
atan	Calculates the arc tangent of x for the current degree/radian mode.
x!	Calculates the factorial of x.
DEC x	Sets the number of decimal places to the value in x.
INTG	Calculates the integer part of x.
FRAC	Calculates the fractional part of x.
RND	Rounds x to the number of digits displayed.
nPr	Calculates the number of ordered ways that x objects can be chosen from a set of y objects.
d/r	Switches between the degree and radian mode.
⇒deg	Converts x from radians to degrees.
⇒rad	Converts x from degrees to radians.
Δ%	Calculates the percent change from y to x.
nCr	Calculates the number of ways that x objects can be chosen from a set of y objects.