Men's Suit & Sport Coat Size Conversions
Suit sizes decoded: chest number plus jacket length
A men's suit or sport coat size pairs one number with one descriptive word — 40 Regular, for example. The number is the wearer's chest measurement in inches; the word describes the length of the jacket, with Short, Regular, Long and Extra Long steps matched to height and torso length. This page presents the typical standard chart converting chest measurements and heights into suit sizes, and it carries an important caution alongside the chart: designers and manufacturers vary their sizing, so the chart is a starting point for trying on, never a substitute for it. Links to the wider size guides — women's, men's and shoe charts — sit alongside for the rest of the wardrobe.
Suits and sport coat sizes typically have one size number and one descriptive word to help designate the garments size. For example, "40 Regular". The number refers to the wearers chest size measurement and the descriptive word such as short, long, extra long refers to the length of the jacket.
Number = Chest Measurement
Descriptive Word = Length of Jacket
Below is a typical standard chart, but it is important to note that designers and manufacturers may have variations to the sizing. It is always critical to try on the garment before making a purchase. Don't rely simply on the measurement standards.
You may also want to learn about suit fabrics if you are in the market to buy a new suit.
Clothing Size Guides
Reading a Suit Size Like a Tailor
The chest number assumes the tape went around the fullest part of the chest, under the arms and across the shoulder blades, snug and level. The length word assumes an honest look at height and proportion: shorter jackets suit shorter frames, longer jackets longer ones, and men between steps usually judge by where the jacket hem falls against the hand and seat rather than by the label alone. A well-chosen starting size still leaves the tailor's work — sleeve length, waist suppression and trouser break are alterations, not size changes — but starting one chest size off makes every alteration harder, which is why the chest measurement, taken carefully, is the number that matters most on this chart.
Why Trying On Is Not Optional
Suit sizing looks standardized from the chart, yet brands cut differently through the shoulder, chest and waist, and modern slim, tailored and classic fits can share a size label while fitting three different bodies. The chart's job is to put two or three candidate jackets in your hands quickly; the fitting room decides between them. Shoulders that end at your shoulders, a chest button that closes without pulling, and a collar that sits against the neck are checks no conversion table can make for you — which is why this page pairs its chart with suiting fabric guidance and the broader size guides for the garments worn with the suit.
Common Questions
What does the number in a suit size mean?
The number is the wearer's chest measurement in inches — a size 40 suit is built for a chest measuring about 40 inches.
What do Short, Regular, Long and Extra Long mean in suit sizes?
They describe the length of the jacket, stepped to the wearer's height and torso length; the same chest number is offered in several lengths.
Can I rely on the size chart instead of trying a suit on?
No. Designers and manufacturers vary their sizing and fits, so the chart is a starting point — trying the garment on before purchase is essential.