Understanding British Military Clothing Sizes

Military clothing sizing can look confusing if you're used to seeing Small, Medium or Large on the label.

British military clothing often uses body measurements in centimetres instead. That means a label such as:

75/80/96

or:

190/104

is giving you useful sizing information rather than an arbitrary clothing size.

At The Old Kitbag, we use the original military size wherever possible because it is generally more accurate than converting everything into conventional retail sizing.

This guide explains how to read the most common military sizes you'll find across our store.

Combat Trousers

British military combat trousers commonly use a three-number sizing system.

For example:

75/80/96

This means approximately:

75 cm – Inside leg
80 cm – Waist
96 cm – Seat

The format is therefore:

Inside Leg / Waist / Seat

So:

80/84/100

means:

• 80 cm inside leg
• 84 cm waist
• 100 cm seat

And:

85/88/104

means:

• 85 cm inside leg
• 88 cm waist
• 104 cm seat

This system is commonly found on British Army combat trousers, including many MTP and DPM trousers.

Trouser Size Conversion

For customers more familiar with inches, dividing the centimetre measurement by 2.54 gives an approximate imperial measurement.

Some common examples include:

These inch measurements are approximate and are intended to make the original military measurements easier to understand.

When possible, choose using the centimetre measurements shown on the garment.

Why is there a seat measurement?

Military trouser sizing doesn't rely on the waist alone.

The seat measurement relates approximately to the circumference around the fullest part of the hips/seat.

That extra measurement helps distinguish between trousers that may have the same nominal waist but are cut for different body proportions.

For example, if you are between two sizes, looking at both the waist and seat can give you a better indication of which pair is likely to fit comfortably.

Jackets, Smocks and Outerwear

Many British military jackets, smocks and other upper-body garments use a two-number size.

For example:

190/104

This usually represents approximately:

190 cm – intended wearer height
104 cm – chest

So the format is generally:

Height / Chest

Another example:

180/96

means approximately:

• 180 cm wearer height
• 96 cm chest

Military outerwear is normally designed to allow for movement and clothing layers underneath, so it may feel more generously cut than an equivalent civilian jacket.

This is particularly relevant for products such as:

• MTP smocks
• waterproof jackets
• Royal Navy foul-weather clothing
• combat jackets
• military outer layers

What does 190/104 mean in conventional sizing?

It is tempting to translate a military size directly into Medium, Large or XL, but we prefer not to treat those conversions as exact.

Two people who both normally wear a retail Large may have very different:

• heights;
• chest measurements;
• sleeve requirements; and
• preferred fit.

A military size such as 190/104 gives considerably more useful information.

Where we provide a Small/Medium/Large equivalent on a product page, it should therefore be treated as an approximate guide only.

The original military measurement remains the best reference.

Beret Sizes

Military berets are considerably simpler.

A beret marked:

58

is designed for approximately a:

58 cm head circumference

Likewise:

Size 56 = approximately 56 cm
Size 57 = approximately 57 cm
Size 59 = approximately 59 cm

How to measure your head for a beret

Use a soft measuring tape and measure around your head:

• approximately 2.5 cm above your eyebrows;
• just above your ears; and
• around the widest part at the back of your head.

Keep the tape snug but not tight.

If the measurement is approximately 58 cm, start with a size 58 beret.

Bear in mind that genuine wool military berets can also vary slightly depending on manufacturer, age and previous shaping.

Dress Trousers

Royal Navy, RAF and other British military dress trousers may also use military measurement codes rather than conventional retail sizing.

Where they use a three-number format such as:

80/84/100

we will explain the measurements on the individual product page.

As with combat trousers, we recommend choosing by the actual stated measurements rather than relying purely on a conventional size conversion.

Shirts and Other Garments

Not every piece of military clothing uses exactly the same sizing system.

Depending on the garment, manufacturer and period, you may encounter:

• height/chest measurements;
• neck sizes;
• waist measurements;
• numeric sizes;
• conventional S/M/L sizes; or
• other military-specific markings.

For that reason, always check the individual product description.

Where a label could reasonably be confusing, we aim to explain what the size means on the product page.

Measuring Yourself

For the best chance of getting the correct size, take your measurements wearing ordinary lightweight clothing.

Inside leg

Measure from the crotch down the inside of your leg to approximately where you want the trouser hem to sit.

Waist

Measure around the point where you naturally wear your trousers.

Keep the tape comfortably fitted without pulling it tight.

Seat

Measure around the widest part of your hips and seat.

Chest

Measure around the fullest part of your chest, keeping the measuring tape approximately level around your body.

Height

Military jacket sizing generally refers to your overall approximate height rather than the physical length of the garment itself.

Don't measure the garment and compare it directly

There is an important difference between a body measurement and a garment measurement.

If trousers are labelled:

80 cm waist

the trousers themselves may measure differently when laid flat because clothing requires allowance for movement and construction.

Likewise, a jacket marked 104 chest does not necessarily mean the physical jacket measures exactly 104 cm around the outside.

Military size labels are primarily intended to identify the body size the garment was designed to fit.

Comparing military kit with your existing clothing

One of the easiest ways to choose a size is to combine your body measurements with a garment you already own and know fits well.

For trousers, compare:

• inside leg;
• waist;
• overall fit.

For jackets, compare:

• your chest measurement;
• your height;
• how loosely or closely you prefer outerwear to fit.

Remember that military outerwear is frequently intended to accommodate additional layers.

What if I'm between sizes?

If your measurements fall between two available military sizes, consider how you intend to wear the item.

For trousers, pay particular attention to the waist and seat measurements.

For outerwear, consider whether you intend to wear:

• a T-shirt only;
• a jumper;
• fleece;
• uniform layers; or
• other clothing underneath.

Where you're unsure about a particular item, contact us before ordering and we'll help interpret the sizing information available for that garment.

Genuine surplus can vary

Military clothing may have been manufactured by different contractors over many years.

As a result, two garments carrying the same nominal size can occasionally differ slightly in:

• cut;
• fabric;
• shrinkage;
• manufacturer;
• production period; or
• previous laundering.

This is normal with genuine military surplus.

Our size information is intended to give you the best practical guide available, but minor variations between individual garments can occur.

Why we keep the original military sizes

You may notice that The Old Kitbag doesn't simply rename every pair of trousers as Small, Medium or Large.

That's deliberate.

A label such as:

75/80/96

contains far more useful information than the word Medium.

Likewise:

190/104

tells a customer much more than simply calling a jacket Large.

Where useful, we may provide an approximate conventional equivalent, but we always recommend using the original military measurements first.

Quick Size Guide

TROUSERS

75/80/96

means:

75 cm inside leg / 80 cm waist / 96 cm seat

JACKETS & SMOCKS

190/104

generally means:

190 cm wearer height / 104 cm chest

BERETS

58

means approximately:

58 cm head circumference

Still unsure?

If you're looking at one of our products and aren't sure what the military size means, contact us:

sales@theoldkitbag.co.uk

Tell us:

• the product you're looking at;
• the military size;
• your relevant measurements; and
• your order number if you've already purchased.

We'll help you interpret the sizing information as accurately as possible.

Proven. Genuine. Trusted.

Military sizing might look complicated at first, but in many cases it's actually more informative than conventional retail sizing.

Once you know how to read the numbers, finding the right genuine surplus becomes considerably easier.

The Old Kitbag
Genuine British Military Surplus

Proven. Genuine. Trusted.