Face Form Finder

Beard Length Chart: mm, Inches, Guard Numbers — and How to Read Your Own Length

Short answer

The chart below tells you what each guard number leaves behind. It cannot tell you what length you are wearing right now — and that is the only number you actually trim from. Measure the hair on your own chin first, then set the guard from that reading.

Common guard and length chart

Numbered guards are a shortcut, not a measurement. If your trimmer prints millimetres on the comb, that printed number is the length it leaves.

GuardLength in mmLength in inchesHow it reads on the skin
No guard / #00.5–1.5 mm0–1/16 inSkin colour with a shadow over it, no length you can pinch
#13 mm1/8 inStrands stand up on their own, and skin still shows between them
#26 mm1/4 inStrands begin to lie over one another instead of standing apart
#310 mm3/8 inSkin stops showing through when you look at it straight on
#413 mm1/2 inThe jaw line reads as shaped rather than shaved
#516 mm5/8 inThe chin edge casts its own shadow on the neck
#619 mm3/4 inVolume starts to show from the side, not just from the front
#722 mm7/8 inThe beard hangs past the jaw line instead of following it
#825 mm1 inFull cover, and the length begins to hide the chin

Measure your own length before you cut

Press the zero mark of a ruler against the skin at the front of the chin and read where the longest hair ends. Measure the hair, not the shadow under it.

Take the same reading under the jaw and again at the sideburn. Those three numbers rarely match, and the chin is the one charts quote.

If your beard curls, pull one strand straight between two fingers before you read it. A coil hides length that is genuinely there.

A cloth tape lies flat on a curved jaw more easily than a steel ruler. Keep it against the skin rather than letting it bridge across the chin.

Take the reading twice, a week apart, before you change any setting. One reading inside a growth cycle tells you very little.

No ruler? Use something with a published thickness

Coins, cards and batteries are made to fixed dimensions, so they work as a rough gauge when the tape is missing.

AnchorIts sizeLands near
Bank card0.76 mm (spec allows 0.68–0.84 mm)inside the #0 band
Dime1.35 mminside the #0 band
Penny1.52 mmtop of the #0 band
Quarter1.75 mmjust past #0
Nickel1.95 mmjust past #0
Two penniesabout 3 mmthe #1 mark
Three nickelsabout 5.9 mmjust under the #2 mark
Six quartersabout 10.5 mmthe #3 mark
AAA battery10.5 mm acrossthe #3 mark
AA battery13.7–14.5 mm acrossbetween the #4 and #5 marks

Two pennies come to 3.04 mm, which is the #1 mark to within a rounding. Three nickels come to 5.85 mm, just short of a #2.

Six quarters and an AAA battery both measure 10.5 mm, and both land on the #3 mark.

Treat the pocket gauge as approximate. Coins are struck to a tolerance and a card is only specified between 0.68 and 0.84 mm, so this method can be off by a fraction of a millimetre.

Measure again after the cut

Measure again the same way after the cut, instead of trusting how short the beard feels. A reading taken afterwards is the only proof the trim did what you asked.

What the chart is for

Use the chart to line your measured length up with the look you want. It answers what a number means, not what you are wearing.

Once you have a measured length, compare it with the face-shape examples in Beard Styles for Face Shapes.

For how long each of those lengths takes to come in, see how long a beard takes to grow.