Ordering a t-shirt online is easy until the size arrives and it does not fit. A medium from one brand can feel like a small from another, and the label alone cannot tell you why. The size chart can. This guide shows you how to take your own measurements, how to read a size chart, and how to choose the right size for each kind of fit, so you get it right the first time.
Why the same size can fit differently
There is no single worldwide standard for t-shirt sizes. Each brand decides what small, medium and large mean, and the cut and fabric change how a shirt wears. A slim fit medium is cut closer than a relaxed fit medium, and an oversized medium is wider than both. That is why the letter on the label is only a starting point, and why the measurements on the size chart matter more.
Body measurements and garment measurements
Size charts come in two kinds, and mixing them up is the most common cause of a wrong size.
- Body measurements describe your body: how big your chest, waist and shoulders are. Charts that say "to fit chest" use these.
- Garment measurements describe the t-shirt itself, laid flat. They are usually bigger than your body, because the shirt needs extra room to be comfortable.
Always check which kind a chart shows. If it lists garment measurements, compare them with a tee you already own and like. If it lists body measurements, compare them with your own body.
The four measurements that matter
Garment measurements, taken on a shirt laid flat. Chest is measured flat, so the full round chest is double that number.
How to measure your own body
You need a soft tape measure (the kind tailors use) and a mirror or a helper. Wear light clothing or measure over a thin t-shirt, stand relaxed, and breathe normally.
Simplified outline. Keep the tape level and snug, but not tight.
- Chest: wrap the tape around the fullest part of your chest, under the armpits and across the shoulder blades. Keep it level all the way round, and note the number.
- Waist: measure around your natural waist. This matters most for slim and muscle fits.
- Shoulder: ask someone to measure straight across your back, from the edge of one shoulder to the other.
- Height: stand against a wall without shoes and note your height. It helps you judge length.
- Write everything down in inches or centimetres, and use the same unit as the size chart.
General t-shirt size chart
This is a general reference for a regular fit t-shirt, showing garment measurements with the shirt laid flat. The chest figure here is the full round measurement, so it is the flat width doubled. Use it to understand the logic, then always check the size chart on the product page you are buying from.
| Size | Body chest (in) | T-shirt chest (in) | Length (in) | Shoulder (in) | Sleeve (in) |
|---|---|---|---|---|---|
| XS | 34 | 36 | 26 | 16 | 7.5 |
| S | 36 | 38 | 27 | 17 | 8 |
| M | 38 | 40 | 28 | 18 | 8.5 |
| L | 40 | 42 | 29 | 19 | 9 |
| XL | 42 | 44 | 30 | 20 | 9.5 |
| XXL | 44 | 46 | 31 | 21 | 10 |
| 3XL | 46 | 48 | 32 | 22 | 10.5 |
| Size | Body chest (cm) | T-shirt chest (cm) | Length (cm) | Shoulder (cm) | Sleeve (cm) |
|---|---|---|---|---|---|
| XS | 86 | 91 | 66 | 41 | 19 |
| S | 91 | 97 | 69 | 43 | 20 |
| M | 97 | 102 | 71 | 46 | 22 |
| L | 102 | 107 | 74 | 48 | 23 |
| XL | 107 | 112 | 76 | 51 | 24 |
| XXL | 112 | 117 | 79 | 53 | 25 |
| 3XL | 117 | 122 | 81 | 56 | 27 |
Garments are measured by hand, so expect a small difference of about 1 inch (2.5 cm) either way. Different styles, fits and fabrics can vary from this table.
How to pick your size
- Find your body chest from the steps above.
- Add room for the fit you want. For a regular fit, the t-shirt chest should be about 2 inches (5 cm) bigger than your body chest. For a snug slim fit, about 1 to 1.5 inches. For relaxed, about 3 to 4 inches.
- Match that number to the t-shirt chest column of the size chart.
- Check the length and shoulder. Compare them with a tee you already own and like.
Size by fit
- Slim and muscle fit: pick your usual size if you want it close to the body, and go one size up if you are between sizes or want more comfort.
- Regular fit: go with the size that matches your body chest on the chart.
- Relaxed fit: your regular size gives an easy fit. Go one size up for a very loose feel.
- Oversized and boxy fits: these are already cut wide, so your regular size gives the intended loose look. Size down only if it looks too big, and size up if you want it even looser. See our t-shirt fit types guide for how each cut looks.
Between two sizes?
This is very common. Use these rules:
- If the shirt is slim or muscle fit, or your shoulders are broad, choose the larger size.
- If it is already relaxed or oversized, choose the smaller size so it does not swamp you.
- If it is a cotton tee, remember it can shrink a little in the first washes, so the larger size is safer for a regular fit.
- If the shirt is stretchy, the smaller size usually works well.
Common sizing mistakes
- Measuring over thick clothes. It adds extra inches. Measure over a thin t-shirt or none.
- Pulling the tape too tight, which makes you choose a size that is too small.
- Mixing body and garment measurements, comparing your body to a flat-shirt number.
- Forgetting the flat measurement is half. If a chart gives chest laid flat, double it to compare with your body.
- Ignoring length. A shirt can match your chest but still be too short or too long for your height.
- Choosing by the letter alone without checking the chart for that particular style.
The easiest method: copy a tee you love
If you already own a t-shirt that fits you perfectly, lay it flat and measure its chest (armpit to armpit), length, shoulder and sleeve. Compare those numbers with the size chart's garment measurements. The closest size is almost always the right one, and this method works for any brand.
Frequently asked questions
How do I know which t-shirt size I am?
Measure your chest around the fullest part, then find the size whose t-shirt chest is about 2 inches (5 cm) larger for a regular fit. Check the chart for each style, because sizes differ between brands.
Is the chest measurement on the chart the full round or the flat width?
It depends on the chart. Garment charts often give the flat width, which you double to compare with your body. The chart should say which one it uses. If it does not, ask the seller.
Should I size up for an oversized t-shirt?
Usually not. Oversized tees are already cut big. Your regular size gives the intended look. Size up only if you want it extra loose.
Will a cotton t-shirt shrink?
It can shrink slightly, mostly in the first few washes, especially if washed in hot water or dried in high heat. Washing in cold water and drying in the shade keeps the fit close to what you bought.
What if my chest and waist fit different sizes?
Choose the size that fits your chest and shoulders, since a t-shirt cannot be adjusted there. A slightly looser waist is easy to live with, and a relaxed or regular fit handles it best.
The bottom line
A good fit starts with a good measurement. Measure your chest and shoulders, decide how loose you want the shirt to be, and match those numbers to the size chart instead of trusting the letter. When in doubt, compare with a t-shirt you already love.
Ordering a t-shirt online is easy until the size arrives and it does not fit. A medium from one brand can feel like a small from another, and the label alone cannot tell you why. The size chart can. This guide shows you how to take your own measurements, how to read a size chart, and how to choose the right size for each kind of fit, so you get it right the first time.
Why the same size can fit differently
There is no single worldwide standard for t-shirt sizes. Each brand decides what small, medium and large mean, and the cut and fabric change how a shirt wears. A slim fit medium is cut closer than a relaxed fit medium, and an oversized medium is wider than both. That is why the letter on the label is only a starting point, and why the measurements on the size chart matter more.
Body measurements and garment measurements
Size charts come in two kinds, and mixing them up is the most common cause of a wrong size.
- Body measurements describe your body: how big your chest, waist and shoulders are. Charts that say "to fit chest" use these.
- Garment measurements describe the t-shirt itself, laid flat. They are usually bigger than your body, because the shirt needs extra room to be comfortable.
Always check which kind a chart shows. If it lists garment measurements, compare them with a tee you already own and like. If it lists body measurements, compare them with your own body.
The four measurements that matter
Garment measurements, taken on a shirt laid flat. Chest is measured flat, so the full round chest is double that number.
How to measure your own body
You need a soft tape measure (the kind tailors use) and a mirror or a helper. Wear light clothing or measure over a thin t-shirt, stand relaxed, and breathe normally.
Simplified outline. Keep the tape level and snug, but not tight.
- Chest: wrap the tape around the fullest part of your chest, under the armpits and across the shoulder blades. Keep it level all the way round, and note the number.
- Waist: measure around your natural waist. This matters most for slim and muscle fits.
- Shoulder: ask someone to measure straight across your back, from the edge of one shoulder to the other.
- Height: stand against a wall without shoes and note your height. It helps you judge length.
- Write everything down in inches or centimetres, and use the same unit as the size chart.
General t-shirt size chart
This is a general reference for a regular fit t-shirt, showing garment measurements with the shirt laid flat. The chest figure here is the full round measurement, so it is the flat width doubled. Use it to understand the logic, then always check the size chart on the product page you are buying from.
| Size | Body chest (in) | T-shirt chest (in) | Length (in) | Shoulder (in) | Sleeve (in) |
|---|---|---|---|---|---|
| XS | 34 | 36 | 26 | 16 | 7.5 |
| S | 36 | 38 | 27 | 17 | 8 |
| M | 38 | 40 | 28 | 18 | 8.5 |
| L | 40 | 42 | 29 | 19 | 9 |
| XL | 42 | 44 | 30 | 20 | 9.5 |
| XXL | 44 | 46 | 31 | 21 | 10 |
| 3XL | 46 | 48 | 32 | 22 | 10.5 |
| Size | Body chest (cm) | T-shirt chest (cm) | Length (cm) | Shoulder (cm) | Sleeve (cm) |
|---|---|---|---|---|---|
| XS | 86 | 91 | 66 | 41 | 19 |
| S | 91 | 97 | 69 | 43 | 20 |
| M | 97 | 102 | 71 | 46 | 22 |
| L | 102 | 107 | 74 | 48 | 23 |
| XL | 107 | 112 | 76 | 51 | 24 |
| XXL | 112 | 117 | 79 | 53 | 25 |
| 3XL | 117 | 122 | 81 | 56 | 27 |
Garments are measured by hand, so expect a small difference of about 1 inch (2.5 cm) either way. Different styles, fits and fabrics can vary from this table.
How to pick your size
- Find your body chest from the steps above.
- Add room for the fit you want. For a regular fit, the t-shirt chest should be about 2 inches (5 cm) bigger than your body chest. For a snug slim fit, about 1 to 1.5 inches. For relaxed, about 3 to 4 inches.
- Match that number to the t-shirt chest column of the size chart.
- Check the length and shoulder. Compare them with a tee you already own and like.
Size by fit
- Slim and muscle fit: pick your usual size if you want it close to the body, and go one size up if you are between sizes or want more comfort.
- Regular fit: go with the size that matches your body chest on the chart.
- Relaxed fit: your regular size gives an easy fit. Go one size up for a very loose feel.
- Oversized and boxy fits: these are already cut wide, so your regular size gives the intended loose look. Size down only if it looks too big, and size up if you want it even looser. See our t-shirt fit types guide for how each cut looks.
Between two sizes?
This is very common. Use these rules:
- If the shirt is slim or muscle fit, or your shoulders are broad, choose the larger size.
- If it is already relaxed or oversized, choose the smaller size so it does not swamp you.
- If it is a cotton tee, remember it can shrink a little in the first washes, so the larger size is safer for a regular fit.
- If the shirt is stretchy, the smaller size usually works well.
Common sizing mistakes
- Measuring over thick clothes. It adds extra inches. Measure over a thin t-shirt or none.
- Pulling the tape too tight, which makes you choose a size that is too small.
- Mixing body and garment measurements, comparing your body to a flat-shirt number.
- Forgetting the flat measurement is half. If a chart gives chest laid flat, double it to compare with your body.
- Ignoring length. A shirt can match your chest but still be too short or too long for your height.
- Choosing by the letter alone without checking the chart for that particular style.
The easiest method: copy a tee you love
If you already own a t-shirt that fits you perfectly, lay it flat and measure its chest (armpit to armpit), length, shoulder and sleeve. Compare those numbers with the size chart's garment measurements. The closest size is almost always the right one, and this method works for any brand.
Frequently asked questions
How do I know which t-shirt size I am?
Measure your chest around the fullest part, then find the size whose t-shirt chest is about 2 inches (5 cm) larger for a regular fit. Check the chart for each style, because sizes differ between brands.
Is the chest measurement on the chart the full round or the flat width?
It depends on the chart. Garment charts often give the flat width, which you double to compare with your body. The chart should say which one it uses. If it does not, ask the seller.
Should I size up for an oversized t-shirt?
Usually not. Oversized tees are already cut big. Your regular size gives the intended look. Size up only if you want it extra loose.
Will a cotton t-shirt shrink?
It can shrink slightly, mostly in the first few washes, especially if washed in hot water or dried in high heat. Washing in cold water and drying in the shade keeps the fit close to what you bought.
What if my chest and waist fit different sizes?
Choose the size that fits your chest and shoulders, since a t-shirt cannot be adjusted there. A slightly looser waist is easy to live with, and a relaxed or regular fit handles it best.
The bottom line
A good fit starts with a good measurement. Measure your chest and shoulders, decide how loose you want the shirt to be, and match those numbers to the size chart instead of trusting the letter. When in doubt, compare with a t-shirt you already love.