Find the inner and outer diameter dimensions of standard imperial and metric pipes. Use our pipe volume calculator to find the volume and weight each of these sizes can hold.
Many products have a name that for convenience only approximates the material’s size. These are
sometimes referred to as nominal dimensions. Webster’s describes nominal as “in name only.” In
other words, you can’t trust the “name” dimensions in actual measurements or calculations.
Differences and difficulties in correctly describing a tube and pipe are common in the
metalworking industry.
Pipe is a commonly used material in the fencing industry, most commonly for chain link fences
and gates. However pipe and tubing are not the same materials! Pipe was originally used for the
movement of water, and therefore the ID (inside diameter) was the critical dimension. The
nominal dimension for pipe is the ID. So, 1½ inch pipe is NOT 1½ inch outside diameter, but
instead is nominally, (approximately) 1½ inch inside diameter. Pipe is typically manufactured to
looser tolerances and less expensive to purchase. However in the fence and construction
industry, where pipe is commonly used, it will often be referred to by its outside dimension,
since fittings, caps and other parts most commonly mate the the outside of the pipe.
This is only a partial list! You can see that all of the materials listed are about 2 inches, but
depending on the tolerance and precision of the tool or mating part, describing all of them as
2-inch pipe is bound to cause problems.
So, given all the possible tube and pipe sizes and all the various names used to describe them,
how is the average person supposed to keep it all straight? Whether you think your material is
tube or pipe, when describing it, remember these key points: