Example 1
- Radius: 5
- Height: 12
376.99
A can r = 5, h = 12. Label 376.99, no bottom or lid.
Cylinder lateral area calculator
Give the base radius and the height of the can. You get the wrap, a rectangle with sides 2πr and h, without the bottom or the lid. At r = 5 the circumference is 31.42, and at h = 12 the label is 376.99.
A = 2πrh. Volume is on the cylinder volume calculator. A cone is on the cone volume calculator.
Result
Radius r (cm) and Height h (cm). Lateral area shows up here.
How it works
Lateral area is the base circumference times height. A = 2πrh unrolls the wall into a rectangle: one side is 2πr, the other is h. The calculator uses π and two decimal places. The result is in cm² or in². The bottom and the lid stay outside this product.
The can on the page has r = 5 and h = 12. Circumference 31.42 times 12 is 376.99. The full surface of a closed can would add two circles: 2πr(h+r) = 534.07. The gap 157.08 is two bases of 78.54 each. Volume at those numbers is 942.48, a different unit on another page. The unit cylinder r = 1, h = 1 has wrap 6.28.
Type the radius, the same r as on cylinder volume, then height from lid to lid. Click Calculate. If you know diameter, divide by two. Diameter 10 means r = 5; typing 10 as r doubles the wrap, because here r is to the first power, not squared as in volume. A comma and a period are the same.
The pair r = 10, h = 2 and the pair r = 2, h = 10 both give 125.66, because 2πrh depends on the product r times h. 10×2 and 2×10 are the same 20. A cone uses slant height, not cylinder height, another calculator. A sphere uses 4πr² and has no h.
Switching to inches relabels the result as in². Both numbers in one unit. If you need the whole can with lids, add 2πr² yourself: at r = 5 that is 157.08 on top of 376.99. This page does not add them.
A can label is that rectangle. Paper width is the circumference, about 31.42 at r = 5, and sheet height is h. Overlap for the glue seam sits outside the formula, same as paint on the lid.
How to use
- Type the base radius, the same r as on cylinder volume, in cm or inches.
- Type the can height, from lid to lid, not a cone slant.
- Click Calculate. At r = 5 and h = 12 you get 376.99, the wrap without lids.
- If you know diameter, divide by two. Typing diameter as r doubles the label.
- With lids it would be 534.07. Add the two circles yourself or compute the full surface elsewhere.
Formula
Alateral = 2 × π × r × h
Base circumference times height. Add two lids 2πr² yourself if you need them.
Lateral area at r = 5 and h = 12
The wrap 2πr × h, no bottom or lid. At r = 5 the circumference is 31.42, and at h = 12 the label is 376.99.
- r
- Base radius. 5 with h = 12 is 376.99. Short and wide r = 10 and h = 2 is 125.66.
- h
- Can height. 12 with r = 5. Volume πr²h at those same numbers is on cylinder volume.
- π
- Inside 2πrh. At r = 5 the circumference 31.42 times h = 12 is 376.99.
- cm²
- The area unit on the metric switch. r = 5 and h = 12 print 376.99, a wrap, not 785.40 of volume.
Examples
Example 2
- Radius: 1
- Height: 1
6.28
Unit cylinder r = 1, h = 1, wrap 6.28.
Example 3
- Radius: 10
- Height: 2
125.66
Short and wide r = 10, h = 2, 125.66.
Example 4
- Radius: 3
- Height: 8
150.80
r = 3, h = 8, 150.80.
Example 5
- Radius: 4
- Height: 4
100.53
r = h = 4, 100.53.
Example 6
- Radius: 2
- Height: 10
125.66
Slim r = 2, h = 10, also 125.66, a different pair from r = 10 and h = 2.
Example 7
- Radius: 7
- Height: 3
131.95
r = 7, h = 3, a short drum.
Example 8
- Radius: 6
- Height: 6
226.19
r = 6, h = 6, 226.19.
Frequently asked questions
How much label at r = 5 and h = 12?
376.99, the side only. With two bases 534.07. The gap 157.08 is two circles of 78.54 each.
Is this the full cylinder surface?
This is the side only, 2πrh. At r = 5 and h = 12 it is 376.99. With two bases it is 534.07.
How do I turn this into a can label?
The result is the wrap area. The label rectangle has sides 2πr and h. At r = 5 the width is about 31.42 and the height is 12.
Is this cylinder volume?
Volume πr²h at 5 and 12 is 942.48 cm³. This page is cm², wall area.
Is diameter 10 the same as r = 10?
Diameter 10 means r = 5. Typing 10 as r doubles the wrap because r is to the first power.
Where are the lids?
Two circles πr². At r = 5 each is 78.54. This page does not add them.
Does a cone have the same lateral area?
A cone uses slant height, not cylinder height. Different page, different formula.
Is sphere 4πr² here?
A sphere has no h. Sphere surface area is on its own page.
Why do r = 10, h = 2 and r = 2, h = 10 both give 125.66?
Because 2πrh depends on the product r times h. 10×2 and 2×10 are the same 20.
Can r and h use different units?
Both in cm or both in inches, result cm² or in². Mixing breaks the scale.
Knowledge sources
The calculator computes the same formula as the definition below.
Page updated in 2026.