Calculators
Capsule Calculator
Calculate capsule volume, surface area, and end-to-end length from radius and straight cylindrical length locally in your browser.
Measure a cylinder with hemispherical ends.
A capsule (spherocylinder) consists of a circular cylinder and two hemispherical ends of radius r. Enter straight cylindrical length L, excluding the ends. Volume = πr²L + 4πr³/3. Surface area = 2πrL + 4πr²; circular joins are internal and excluded. Total end-to-end length = L + 2r. For r = 2 and L = 6, volume is 104π/3 ≈ 108.908545324 cubic units, area is 40π ≈ 125.663706144 square units, and total length is 10 units. Zero straight length gives a sphere. Use consistent units; radius must be from 1e-50 to 1e50 and straight length zero or from 1e-50 to 1e50. Scientific notation is accepted. Results use browser floating-point arithmetic rounded to 12 significant digits. This models a solid capsule; hollow container capacity requires internal dimensions. Inputs stay in your browser.
Frequently Asked Questions
Everything you need to know about this tool, how it works, and privacy.
Which length should I enter?
Enter only the straight cylindrical length. If you have total end-to-end length, subtract twice the radius first.
How are volume and surface area calculated?
Volume is πr²L + 4πr³/3 and surface area is 2πrL + 4πr². The two hemispheres make one sphere; the circular joins are not exposed.
Can straight length be zero?
Yes. Zero straight length gives a sphere. Radius must remain positive.
What units should I use?
Use the same unit for both lengths. Area uses square units and volume uses cubic units. Divide a diameter by two before entering the radius.
Does this measure hollow container capacity?
This models a solid shape. Interior capacity requires internal measurements; wall thickness is not included.
Are my measurements uploaded?
No. Calculation, reset, and copying run locally in your browser.