Math

Surface Area Calculator

Surface area of common 3D shapes.

Enter your values

Choose one of: Rectangular box, Cylinder, Sphere, Cone.

Enter the length / radius you are working with.

Enter the width you are working with.

Enter the height you are working with.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
Surface area
248
Volume
240
Surface to volume ratio
1.03333
Shape
Rectangular box

Quick answer

Surface area is the total area of all faces or curved surfaces enclosing a solid.

At a glance

What it doesSurface area of common 3D shapes.
CategoryMath
Inputs neededShape, Length / radius, Width, Height
Main outputSurface area
CostFree — no sign-up, no download

How to use the Surface Area Calculator

  1. 1Choose the solid shape.
  2. 2Enter the dimensions it needs (radius uses the first field).
  3. 3Read area and volume.

Inputs explained

Shape
Choose one of: Rectangular box, Cylinder, Sphere, Cone.
Length / radius
Enter the length / radius you are working with.
Width
Enter the width you are working with.
Height
Enter the height you are working with.

Worked example

Using the values the calculator loads with:

Inputs

  • ShapeRectangular box
  • Length / radius6
  • Width4
  • Height10

Results

  • Surface area248
  • Volume240
  • Surface to volume ratio1.03333
  • ShapeRectangular box

Frequently asked questions

Why does surface to volume ratio matter?

It drives heat loss, drying and reaction rates — small objects lose heat fastest.

Which fields do spheres use?

Only the radius field.

What do I need to enter into the Surface Area Calculator?

Just 4 values: shape, length / radius, width, height. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the Surface Area Calculator work out the answer?

Surface area is the total area of all faces or curved surfaces enclosing a solid. The working is shown step by step so you can verify the result by hand.

Is the Surface Area Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.