Lock & Co. are proud to launch a new limited edition James Bond hat. View


Why hat size matters

Hats are not just stylish fashion accessories; they also serve a practical purpose by providing protection from the elements and adding a finishing touch of style to your outfit. However, to ensure a hat fits comfortably and is flattering, it's essential to know your hat size. In this article, we'll guide you through the process of accurately measuring your hat size so you can confidently choose the perfect headpiece for any occasion. Your perfect hat deserves the perfect fit.

How are hat sizes measured?

Hat sizes are typically measured using the circumference of the head and then compared to a hat size chart for conversion.

How do I measure for my hat size?

To measure your hat size, here’s what you'll need:

  • Soft measuring tape
  • Mirror (optional)
  • A friend to help if possible

  1. Stand in front of the mirror and locate the widest part of your head. It is essential to find this spot, as that's where the hat will sit.
  2. Make use of a flexible tape measure. When measuring for a cap or a hat, you want to measure on finger above the brow and one finger above the ear to the largest point on the back of the head. When measuring for a Bakerboy cap, you want to measure just below that point because it sits deeper on your head. Make sure the tape is snug but not too tight. You should aim for a comfortable fit that doesn't press into your skin.
  3. Measure the circumference of your head in centimetres or inches and note down the number. Then, using your measurement, find your corresponding hat size on our hat sizing chart (as seen below) that sets out the hat sizes for men’s hats and women’s hats.
  4. With your hat size in hand, you can confidently select hats that are the perfect fit. Remember that some hats come in small, medium, and large sizes, while others use specific measurements.


Our hat sizing video takes you through the instructions step by step:

Additional Considerations:

  • Hat Styles: Different hat styles may fit differently, even with the same measurements. For example, a baseball cap will have a more snug fit than a slouchy beret. Read our tips from our Hatters for individual hat styles.
  • If you're between sizes, generally, opt for the larger size, as you can always add padding or adjust the fit with inserts.
  • Consider the hat material. Some materials are more stretchy than others, so factor this into your decision.


Knowing your hat size will help you find the perfect fit and the perfect hat for a comfortable and stylish look. By following these simple steps to measure your head and converting the measurement into a hat size, you can confidently choose the perfect hat for any occasion. So go ahead and explore our range of luxury hats born out of fashion and functionality.

View Lock & Co.'s Bestsellers


Lorem ipsum dolor sit amet consectetur. Egestas nisi sollicitudin lacus venenatis dui.

View all

  • Top tips on buying hats for bigger heads: Find the best style, comfort, and fit at Lock & Co.

    Here's your comprehensive Lock & Co. guide to choosing hats that fit well in a larger size.

  • The Rake magazine's international issue

    We love this photoshoot featuring our boaters and Florida flat cap for The Rake magazine.

  • The Lock & Co. Guide to Panama Hats

    Learn about Lock & Co.'s exclusive Panama hats, which are handwoven in Ecuador by craftsmen and women utilising methods that have been passed down through generations.

  • Wedding Hat Etiquette

    Rules surrounding wedding guest millinery are not what they once were however here at Lock & Co. Hatters we firmly believe that choosing the right piece is both a decision of style and etiquette.

  • The timeless appeal of a luxury Panama hat

    This summer, embrace the timeless appeal of a luxury Panama hat.

  • A Royal Warrant of Appointment to King Charles III

    Lock & Co. is tremendously honoured to have been granted a Royal Warrant of Appointment to His Majesty King Charles III as hatters.


    On the 26th  of October 2022, Lock & Co. opens ‘60 Years of James Bond Hats’, an exclusive exhibit celebrating the film franchise’s 60th Anniversary.


    Our Estate Faux Fur Hat, Tiffany Drop-Brim Hat and Gill Tweed Flat Cap look great in this shoot for the June 2024 issue of Tatler Magazine.

  • Packable & Rollable Hats Guide

    We have the solution to all your travel chapeau woes! From Panamas and sun hats to bucket hats and trilbies, these hats have been designed specifically for traveling and won’t lose their shape when packed into a suitcase, so there’s no need to leave your favourite hat behind…