How long will a blade leave the coat?
The length a blade leaves a dog's or horse's coat is usually etched on the face of the blade. On our website the blade number and the coat length is included in the blade name, and again in the product description, and you'll also see it on the blade photo. Blade manufacturers usually give measurements in millimetres (mm's) and in inches, but the length the coat will be does depend what direction you clip. More about that below.
Popular blade lengths
Size 3 > 13mm to 19mm
Size 4 > 8mm to 9.5mm
Size 5 > 6mm to 6.3mm
Size 7 > 3mm to 4mm
Size 8 > 2.8mm
Size 9 > 2mm
Size 10 > 1.5mm to 1.8mm
Size 15 > 1.2mm to 1.5mm
Size 30 > 0.5mm
Size 40 > 0.1mm to 0.25mm
Size 50 > 0.2mm to 0.05mm
Toe blade > 0.5mm to 0.8mm
Why do blades with the same number have different lengths?
The blade number does not tell you the length the coat will be. For example, a size 10 blade will leave the coat under 2mm. An Andis, Laube, Shernbao or Smart Coat size 10 blade leaves the coat 1.5mm, but a Buttercut Geib size 10 is 1.6mm, and the Wahl 10 blade is 1.8mm. Yet all are size 10 blades.
Does the direction you clip the coat matter?
Yes, if you clip with the direction the coat grows, the resulting coat length will be longer than what the blade says. If you cut against the direction the coat grows, the coat length will match what the blade says. Blade manufacturers give their measurements for coat length based on the shorter length, so they tell you what the coat length will be when you clip against the direction the coat grows.
When clipping with the direction the coat grows, the resulting length will be about twice as long. So a size 7 blade which says it leaves the coat 3mm, will result in the coat being around 6mm when clipped in the same direction the coat grows. Clipped against the direction of the coat, a 7 blade will result in a 3mm coat length.
TIP: To keep the head looking well balanced in proportion to the body when clipping dogs, clip the head using a longer blade than the body. Some groomers use a 'rule of two' meaning they go up two blade sizes for the head. So if you clipped the body with a 7 blade (3mm), you might use a 5 blade (6mm) or 4 blade (8mm) on the head depending on the look you want. For the coat where the different body and head lengths meet, you can then finish with thinning scissors to smoothly blend the two lengths.