Number 4 Haircut: Short but Full, and Good for Dense Hair and Cowlicks

Where a 4 sits between buzz and scissor length

A 4 is the boundary between a clipper cut and a scissor cut. Below it, hair stands mostly upright and reads as a buzz. At 13 mm, most straight hair has enough weight to fold over and lie in its growth direction, so it starts to look like a very short conventional haircut.

Above a 4, standard guards cut less evenly, especially on thick hair, and barbers tend to switch to clipper over comb or scissors. That makes a 4 the longest length you can reliably reproduce at home with a guard.

Why dense and coarse hair looks better at a 4

Very dense hair cut to a 1 or 2 can look like a dark helmet with a hard edge, and it grows back fuzzy within days. At a 4, the same density lies flatter and softer, and the extra length makes regrowth less noticeable week to week.

Coarse hair also tends to stand straight out at short lengths, which can look spiky. A 4 gives it enough length to bend. If it still pushes out at the sides above the ears, we can thin the bulk with a detailer or thinning shears so the silhouette stays close to the head. Our guide to haircuts for thick hair covers bulk removal in more depth.

The cowlick problem, and why 13 mm helps

A cowlick is a patch where hair grows in a spiral or against the surrounding direction, usually at the crown or the front hairline. At about 5 to 8 mm, it is long enough to lift but too short to fall over, so it sticks up as a tuft.

At a 4, the hair in the whorl is heavy enough to lie down in its spiral, and the swirl looks like texture rather than a mistake. That is why we often suggest a 4 on the crown even when the rest of the cut is shorter. For stubborn front or double crowns, see haircuts for cowlicks.

Scissor tops that pair with a 4 on the sides

A 4 on the sides creates a gentle, low-contrast frame that suits classic tops cut with scissors. The table shows the pairings we cut most.

Getting the blend right between a 4 and a scissor top

The risk with a 4 under a much longer top is a visible shelf where the clipper length stops and the scissor length begins. We avoid it by cutting the upper sides with clipper over comb or scissor over comb, working the weight line up into the top.

At the bottom, a 4 needs tapering to look intentional. We step down through a 3 and a 2 at the nape and sideburns, then clean the neckline. Skin is rarely used under a 4, since the jump is large and the soft look is usually the point. Our scissor cuts service covers this kind of finish.

Upkeep and growing out from a 4

Because a 4 is already long enough to lie flat, a few extra millimetres barely change the look. Most people find it stays neat for four to five weeks, with the neckline and ears the first places to look overdue.

It is also the easiest short cut to grow out of. From a 4, you are about a month away from enough length to side part, and two to three months from a medium cut, with no awkward stage where bare skin fills in.