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Solid rod & bar calculator
The material volume of a solid round rod or bar from its diameter and length — handy for weight and stock estimates.
A solid round rod or bar is a cylinder, and its volume is the material it is made of. This solid rod & bar calculator takes the diameter and length and returns that material volume — a first step toward stock and weight estimates.
How to work it out
- Measure across the circular end — the diameter or radius.
- If you measured the diameter, halve it to get the radius r.
- Square the radius and multiply by π to get the base area.
- Multiply the base area by the height h: V = π r² h.
- Convert the result into your preferred unit above.
Worked example. Take a cylinder with a diameter of 10 cm (so a radius of 5 cm) and a height of 25 cm. The base area is π × 5² = 78.54 cm², and multiplying by the height gives a volume of about 1.96 litres (1,963 cm³ · 0.52 US gallons).
For anything that holds liquid, measure the inside of the cylinder — the wall takes up space that the contents cannot.
Every solid rod & bar page
Each page below targets a specific question and opens with the calculator ready to go:
Frequently asked questions
How do I find the volume of a round rod?
V = π r² h, using the rod's radius and its length. Add a metal density to estimate the weight.