How to Measure for a Flat Cap

Getting the right size is the key to a perfect fit. Here’s how to measure your head accurately and choose the right flat cap size.

Our Guide to Measuring

We recommend using a flexible dressmaker’s tape for most accurate result.

Step-by-Step

Use a Flexible Tape Measure: A dressmaker’s tape is ideal.
Position the Tape: Place it around your head about 2 cm above your eyebrows and ears — where a hat would naturally sit.
Check the Measurement: Make sure the tape is level all the way around.
Take Note in Centimetres: Most flat cap sizes are given in cm for accuracy.

Not sure how it should feel? Read our guide: How Should a Flat Cap Fit?

Determining the Correct Size

Compare your head measurement to Lock & Co.’s sizing chart.
If you are between sizes, size up for comfort, you can fine-tune the fit with hat tape.

Are Flat Caps True to Size?

Lock & Co.’s flat caps are generally true to size, but personal preference matters:

Snug Fit: Good for windy weather or active use.
Slightly Looser Fit: Comfortable for all-day wear or warmer months.

Are Flat Caps Adjustable?

Most high-quality flat caps are not adjustable — they are cut to size. That is why measuring your head carefully before ordering is so important.

Explore Further

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Trending Flat Cap Styles in 2025 →

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