A number 1 clipper guard is 3mm, a 2 is 6mm, a 3 is 10mm, a 4 is 13mm and an 8 is 25mm, about an inch. Those sizes hold for Wahl, BaByliss and Andis from a 1 upwards; Philips and Remington set lengths in millimetres instead.
Andis numbers its shortest guard differently, so check the brand before you copy a barber's number. The chart below covers the guard brands, the second table covers Philips and Remington, and the converter does the sum for you.
What size is each clipper guard in mm?
Each full number adds about 3mm, from 3mm for a 1 up to 25mm for an 8, and the half guards sit in between at 1.5mm (a 0.5) and about 4.5mm (a 1.5).
Scroll the table sideways to see every brand.
| Number | Length | Wahl | BaByliss Super-X | Andis | What it looks like |
|---|---|---|---|---|---|
| No guard (0) | 0.5 to 1.7mm | 0.8mm closed | 0.8mm, 1.4mm open | Master blade 0.5 to 2.4mm | Skin-close stubble, the base of a skin fade |
| 0.5 (half) | 1.5mm (1/16 in) | #0.5 | #0.5 | #0 | Scalp clearly visible |
| 1 | 3mm (1/8 in) | #1 | #1 | #1 | Short buzz, scalp shows through |
| 1.5 (half) | 4.5 to 4.8mm (3/16 in) | #1.5 | #1.5 | #1A | Blending step between a 1 and a 2 |
| 2 | 6mm (1/4 in) | #2 | #2 | #2 | Classic short back and sides |
| 3 | 10mm (3/8 in) | #3 | #3 | #3 | Covers the scalp on most hair |
| 4 | 13mm (1/2 in) | #4 | #4 | #4 | Soft and full, no scalp showing |
| 5 | 16mm (5/8 in) | #5 | #5 | #5 | Starts to lie flat |
| 6 | 19mm (3/4 in) | #6 | #6 | #6 | Crew cut top length |
| 7 | 22mm (7/8 in) | #7 | #7 | #7 | Short crew cut or Ivy League top |
| 8 | 25mm (1 in) | #8 | #8 | #8 | The longest standard guard |
Sources: Wahl UK cutting-length and comb pages, the BaByliss Super-X Metal 7700U instruction booklet, Andis comb set listings (23575 and 01380). Checked September 2026. Andis's 7-comb set skips the 5 and 7.
What do clipper guard numbers mean?
The number is the length the guard leaves in eighths of an inch: a 1 leaves 1/8 inch (3mm), a 2 leaves a quarter inch (6mm) and an 8 leaves a full inch (25mm).
That's why the "3mm per number" rule you'll hear in barbershops works up to a 2 and then drifts. A number 3 is 10mm, not 9mm, and a number 8 is 25mm, not 24mm, because the guards are made in eighths of an inch. The difference is small on the sides, but it's the reason a "number 3 all over" can look longer than you expected.
What number is a 3mm clipper guard?
A 3mm guard is a number 1 on Wahl, BaByliss and Andis alike. For any other length, type it into the converter below and it finds the nearest guard on each brand.
Guard number to mm converter
Pick your clipper brand and a guard number to see the length and the matching guard on the other brands. Or type the length you want in millimetres to find the nearest guard.
Why Andis numbers are different
Andis calls its 1.5mm guard a number 0. On a Wahl or BaByliss, the same 1.5mm guard is a number 0.5, and "zero" means no guard at all. From a 1 upwards the three brands line up. So if a barber used an Andis #0 on your sides and you try to copy it at home with a Wahl, you want the #0.5, not the bare blade. Andis also sells a #1A (3/16 inch) as its half step between 1 and 2.
The Andis Master, a clipper you'll see in plenty of UK barbershops, ships with no guards at all. Its adjustable blade runs from about 0.5mm to 2.4mm, so a barber can go shorter or longer than a standard "zero" just by moving the lever.
Philips and Remington: lengths in mm, not numbers
Most Philips and Remington home clippers use one adjustable comb with a dial or slider, marked in millimetres. That's easier once you know the length you want, so use the chart above to translate your barber's number.
| Clipper | Length range | Steps |
|---|---|---|
| Philips Series 3000 (HC3505) | 0.5mm to 23mm | 13 settings, 2mm steps |
| Philips Series 5000 (HC5632) | 0.5mm to 28mm | 28 settings, 1mm steps |
| Philips Series 7000 (HC7650) | 0.5mm to 28mm | 1mm steps from 3mm, plus a 2mm comb |
| Philips Series 9000 (HC9450) | 0.5mm to 42mm | 400 settings, 0.2mm steps up to 7mm |
| Remington Power-X5 (HC5000) | 0.5mm to 35mm | 72 lengths across 4 combs, including a 1 to 5mm fade comb |
From Philips UK and Remington UK product pages, September 2026.
A Philips set to 6mm and a Wahl #2 cut to the same length. A setting of 10mm is a number 3, and 13mm is a number 4. The main difference you'll notice is on odd lengths: a Philips can do 8mm, which sits between a 2 and a 3 and has no standard guard.
What is the smallest clipper guard?
The smallest standard guard is a 0.5, which leaves 1.5mm (1/16 inch); anything shorter means taking the guard off.
That bare blade is what barbers mean by a "zero". On Wahl and BaByliss clippers it cuts to about 0.8mm, or up to about 1.4mm to 1.7mm with the taper lever open. Andis is the odd one out again: its #0 is an actual guard that cuts to 1.5mm, the same as a Wahl 0.5. For smoother than a bare blade you need a shaver, which our head shaver guide covers.
What is the biggest clipper guard?
A number 8, at 25mm or one inch, is the longest guard on the chart above. Above an inch, barbers usually switch to scissors over comb. Clippers with an adjustable comb go further: the Philips Series 9000 reaches 42mm and the Remington HC5000's long comb 35mm.
What to ask for, number by number
These are the phrases a UK barber will understand straight away. If you're not sure of the style names, our plain English haircut glossary explains each one.
- "Skin fade" or "bald fade" means no guard at the bottom, often foil-shaved, blended up through a 0.5 and a 1. Our skin fade price guide covers what it costs.
- "Number 1 all over" is a very short buzz. Expect to see scalp, and expect it to look shorter on fair or fine hair.
- "Number 2 back and sides, scissors on top" is the standard British short back and sides.
- "Number 3 all over" is the most common buzz cut that still hides the scalp.
- "Number 4 on the sides, tapered" gives soft sides with no visible line. It's a good first request if you're unsure.
- "Grade 6 or 8 on top" suits a crew cut. Anything longer than an 8 is usually cut with scissors.
Half guards: when you need a 0.5 or 1.5
Half guards exist for blending. When a barber goes from a 1 to a 2, the jump from 3mm to 6mm can leave a visible line. A 1.5 (about 4.5mm to 4.8mm, depending on the brand) splits the difference. Half guards come in the box with most Wahl and BaByliss kits. Cheaper home kits often skip them, so check before you buy. Our hair clipper guide lists the guards each clipper comes with.
The taper lever does the same job in smaller steps. Opening the lever on a Wahl or BaByliss adds roughly 0.6mm to 1mm to whatever guard is fitted, so a #1 with the lever open is about 3.6mm to 4mm.
Why the same number can look different
- Hair colour matters. A number 2 on dark, thick hair looks darker and fuller than a number 2 on fair or grey hair, where more scalp shows through.
- Direction matters. Clipping against the growth cuts closer than clipping with it, so the same guard can take off a millimetre more.
- Guards wear and flex. Old plastic guards bend on dense hair and cut slightly shorter.
- Barbers go down in steps. A barber asked for "a 3" may use a 3 on the sides and blend with a 2 at the neckline, which is part of why it looks tidier than a home cut.
Are clipper guards universal?
No: the lengths are close to universal, but the fittings aren't. Wahl guards fit Wahl clippers, and Andis guards fit Andis blades, so buy guards made for your clipper model.