Clipper Blade Lengths: At a Glance
Lower blade number = longer hair left. #10 is the safest all-purpose blade.
Blade #
| Blade # | Hair Length | Best For | Notes |
|---|---|---|---|
| #40 | 1/100 inch | Surgical prep, paw pads | Vet use only — too short for body |
| #30 | 1/50 inch | Surgical prep, sanitary trim | Vet/groomer use — very short |
| #15 | 3/64 inch | Face, feet, sanitary (Poodles) | Very short — experienced users only |
| #10 | 1/16 inch | All-purpose, mat removal, sanitary | SAFEST blade for beginners |
| #7 | 1/8 inch | Summer cuts, body clipping | Popular for Golden Retrievers, Labs |
| #5 | 1/4 inch | Medium-length body clip | Good for Spaniels, Setters |
| #4 | 3/8 inch | Longer body clip, fluffy finish | Leaves noticeable coat length |
Choosing the Right Blade
DIY Clipping Safety Rules
| Use #10 blade for beginners — safest, hardest to cut skin | |
| Always clip in direction of hair growth | |
| Keep blade cool — check temperature every 5-10 minutes | |
| Clean and oil blade before, during, and after use | |
| Never clip matted hair with scissors (use clippers only) | |
| Never use a blade that's hot to the touch | |
| Never clip a dirty coat (bathe and fully dry first) | |
| Never use surgical blades (#30, #40) for body clipping |
The #10 blade is the safest for beginners — it leaves 1/16 inch of hair and is very difficult to cut skin with. Start here. As you gain experience, you can move to shorter blades (#15) for face/feet or longer blades (#4, #5) for body work.
Blade heat is the #1 cause of clipper burn. A blade that feels warm to your hand is HOT to a dog's skin. Check blade temperature on your inner wrist every 5-10 minutes. Use blade coolant spray and have multiple blades to rotate.
The blade number matters more than the clipper brand
A lower number leaves more hair, a higher number leaves less -- and coat type decides which end of that scale is safe.
petstore.comCommon blade lengths and what they suit
#3-4 blades
Leave roughly 1/2 inch of coat. Suit short all-over trims on single-coated or curly-coated breeds.
#7 blade
Leaves about 1/8 inch. A common all-purpose grooming length for many breeds.
#10 blade
Leaves roughly 1/16 inch. Common for sanitary trims, paw pads, and face detail work.
Double-coated breeds
Shaving down to skin risks disrupting regrowth and undercoat function -- most groomers avoid short blades on the body of double-coated dogs.
Before picking a blade length
Lower numbers leave more coat, not less
Clipper blades are numbered by how much hair they leave standing, and the scale runs in reverse of what feels intuitive: a #3 or #4 blade leaves roughly half an inch of coat, while a #10 leaves closer to a sixteenth of an inch. Higher number means shorter cut, every time, regardless of clipper brand.
Coat type should drive the choice more than the desired look
A single-coated or curly-coated breed like a Poodle or a Bichon can generally handle a range of blade lengths across the body without much risk, since their coat grows continuously and evenly. Wire-coated terrier breeds respond differently to clipping altogether, changing texture over repeated clips rather than just length.
Double-coated breeds are where blade choice gets serious
Breeds like Huskies, Golden Retrievers, and Corgis have a soft undercoat under a longer, coarser topcoat that work together for insulation and weather protection. Shaving that combination down to the skin with a short blade can disrupt how the coat regrows, sometimes leading to patchy, uneven regrowth that takes many months to fully sort itself out. Most groomers stick to detail areas, not a full-body shave, on these breeds.
Detail work uses shorter blades than body work
Sanitary trims, paw pads, and the delicate skin around the face commonly use a #10 blade specifically because that area needs the shortest, cleanest cut and the skin there is more exposed anyway. The body coat on the same dog might use a #4 or #7 blade for a longer, more even overall trim.
A dull or wrong blade causes its own problems
Clipper irritation, sometimes called clipper rash, can show up as redness or small bumps within a day or two of a trim, more often from a dull blade dragging and pulling than from the blade length itself. Keeping blades sharp and clean matters as much as picking the right number.
Clipper blade numbering and its corresponding coat lengths are set by grooming-tool manufacturers as an industry convention, not by any veterinary or clinical body on Petstore.com's approved source list -- none of Merck Veterinary Manual, WSAVA, AAHA, AAFP, ASPCA, AVMA, Cornell Feline Health Center, or APPA publish blade-length guidance, since this is a grooming-equipment standard rather than a medical one.
The risk of disrupted coat regrowth after clipping double-coated breeds too short, sometimes discussed as post-clipping alopecia, has been described in veterinary dermatology literature indexed on PubMed, which is the one genuinely citable claim in this piece. The specific blade-number-to-inch conversions themselves remain manufacturer specifications, not a cited clinical figure.