How to measure yourself for a suit
There's a simple way to determine your suit jacket size based on your pants waist size, since most men's suiting is sold as a jacket and pants set.
A set will usually come with either a 6- or 7-inch drop, which is the difference between your jacket and pant size. For standard fits, this means you would add six inches to your waist measurement to determine your chest measurement, or jacket size.
"So if you're a 42 jacket, it will come with 36 pants," Martinez says.
To determine your pant length, or inseam length, consider your height. Suits tend to come in three lengths: short, regular, and long.
"If you're 5'7" and under, on average, you'll be a short, if you're 6'2" and up, you'll be looking at a long, in the middle of these heights, you're a regular," Martinez says.
If you know you don't fit into off-the-rack sizing—for example, if your chest is much larger than your waist—he recommends shopping for separates.