We’re constantly getting asked about hard hat sizing. Through our customer service chat 💬, phone calls 📱, or even on social media.
Here’s the deal. It’s super simple.
All you need to know is this.
SUSPENSION.
📖 Let’s start from the very beginning…
Every hard hat comes with some form of a suspension. A suspension is the piece that is connected to the underside of the hard hat. The suspension is what rests on your head. In other words, the suspension is the headband or headpiece.
The purpose of the suspension is that the hard hat should not lay directly on your head; it suspends the hard hat on top of your head. This way, in the event of a fall or hit, the suspension absorbs the shock instead of the head receiving the impact. When the hard hat is hit, the impact gets distributed into the suspension. Almost like shocks on a car. Smart, right?
👷 How Suspensions Fit
In order for the suspension to absorb impact properly and effectively, the hard hat suspension needs to fit properly. It cannot be too loose or too small, otherwise it will not work.
To make sure the suspension fits just right, they all have sorts of adjustable closures so that the hard hats can fit an array of head sizes. Some closure mechanisms are better than others of course, just like everything else in this Universe. (Think double-sided tape vs. Velcro)



For starters, there is the simple pin lock suspension – the old male/female concept where the little pin gets inserted into the opposite hole. Then there is the glide lock suspension which is when you tug on the suspension to tighten it. The ridges on the glide lock suspension hold the adjustment in place. Perhaps the most common, and definitely the most-liked, is the ratchet suspension. The ratchet is a knob which can be turned just so to adjust the size of the headband smoothly and accurately.
📏 Sizing – The Long and Short of It:
Most hard hats to don’t have an official size like Small, Medium or Large since they are adjustable. The typical adult hard hat suspension is adjustable from 6.5 to 8 inches.
(Click here for our article on accurate head measurement!)
We hope this article was helpful to you! Stay tuned for our article on Hard Hat Expiration – another super common question.