Quick Take: Measure around the base of your bare neck with a flexible tape, keeping it level and snug without pressing into the skin. Record the measurement, then follow the shirt's size guide for any comfort allowance. Check whether its chart lists body measurements or finished collar measurements before choosing your size.

A formal shirt can fit neatly through the shoulders and chest yet become uncomfortable the moment you fasten the top button. Measuring your neck helps you avoid that problem, particularly when you plan to wear a tie. The important part is not simply getting a number. You also need to understand what the size chart expects that number to represent.

This guide focuses on neck and collar fit rather than a complete shirt fitting. You will still need to check chest, sleeve and body measurements, but getting the collar right gives you a much stronger starting point.

What do you need to measure your neck?

Use a flexible dressmaker's measuring tape, a mirror and somewhere to note the result. A second person can help you keep the tape level, although you can take the measurement yourself. Remove ties, scarves and anything else sitting around your neck.

If you do not have a flexible tape, use a non-stretch piece of string and measure it against a ruler afterwards. Avoid elastic cord, which can change length as you pull it. A rigid builder's tape is awkward to position around the neck and is not the best tool for this job.

How do you measure your neck step by step?

1. Stand naturally. Keep your head level, shoulders relaxed and chin in its normal position. Do not stretch your neck upwards.
2. Find the collar position. Place the tape around the base of your neck, where a closed shirt collar would sit, rather than high beneath your jaw.
3. Keep the tape level. Check the back and sides in a mirror, or ask someone to help. Do not let it twist or slope down your chest.
4. Take a snug body measurement. Let the tape rest against the skin without digging in. Do not deliberately add a finger gap at this stage.
5. Read and record. Note the number and the unit, then repeat the measurement to check consistency.
6. Consult the product's guide. Apply a comfort allowance only if the guide asks for one, and distinguish body measurements from finished garment measurements.

If the readings differ, check your posture and tape position before averaging anything. A careful second attempt is more useful than guessing which number looks right.

Should you put a finger under the tape?

Some measuring instructions ask you to place a finger beneath the tape to build in room; others ask for a close body measurement and account for ease in the size chart. Both approaches can work within their own sizing systems. Problems arise when you mix them.

For a repeatable starting point, record your snug neck circumference without extra room. If a particular brand asks for a finger allowance, take a separate measurement using that method and label it clearly. Do not add a finger gap and then add another allowance unless the instructions explicitly require both.

The finger test is more useful as a rough check on a shirt you are wearing than as a precise measurement. Finger widths vary, so comfort, movement and the product's measurements remain important.

How do you convert centimetres to inches?

To convert centimetres to inches, divide by 2.54. To convert inches to centimetres, multiply by 2.54. Keep the original reading rather than rounding it early: small differences matter around a fastened collar.

For example, a 40 cm neck measurement is approximately 15.75 inches. That is a conversion of your measurement, not an automatic instruction to buy a particular collar size. The final choice depends on whether the retailer's chart describes your body or the finished collar, and how it handles comfort allowance.

Do not assume a European label and an inch-based label are exact equivalents across every brand. Compare the actual chart supplied for the shirt you are considering.

What if your measurement falls between sizes?

Start with the manufacturer's guidance. If the chart uses body measurements, see which size range includes your neck measurement. If it gives finished collar measurements, compare those with the required wearing room rather than selecting a collar that exactly matches your bare neck.

Where the guidance recommends choosing the larger collar between sizes, follow it, then check the chest and shoulders too. A larger collar may come with a larger body. If that creates a poor fit elsewhere, another cut or model may be a better solution than simply sizing up again.

How should a formal shirt collar feel when fastened?

Fasten the top button without a tie first. You should be able to turn your head, swallow and sit normally without the collar pressing uncomfortably into your neck. It should also sit neatly rather than leaving a conspicuous gap.

Then add the tie you intend to wear. The knot should sit neatly in the collar opening without being tightened to compensate for a loose collar. If the shirt feels comfortable only when the top button is open, it is not a good closed-collar fit for you.

Try the shirt with your jacket and sit down as well as standing. The outfit needs to work in use, not just for a quick look in the mirror.

Can you measure a shirt that already fits?

Yes, as a useful comparison. Unbutton the collar and lay it flat without stretching it. Measure along the inside collar band from the centre of the button to the point on the buttonhole where the button rests when fastened. Follow any different method specified by the retailer.

This is a finished garment measurement, not your body circumference. Keep the two figures separate. Use a shirt that fits comfortably when clean and ready to wear; an old shirt that has shrunk or stretched may be a misleading reference.

Which Wessi shirts can you compare after measuring?

These options serve different occasions. Check each product's current size guide and available sizes rather than assuming the same letter size guarantees the same collar measurement.

What other measurements should you check?

A comfortable collar cannot correct a tight chest or short sleeves. Check shoulder position, sleeve length and the room you need through the torso. Browse men's shirts by style, then use the individual sizing information to narrow your choice.

When pairing a shirt with men's suits, try the layers together. Follow the care label after purchase and avoid assuming an unverified shrinkage percentage. Accurate measurement, the right chart and a proper try-on are more useful than a universal size rule.