Dog Clipper Blade Numbers Explained: How to Pick the Perfect Length and Keep Blades Running Smoothly

November 26, 2025

When you’re grooming day in and day out, the right clipper blade can make all the difference. Not just to the finish of the coat, but to your comfort and confidence too. Understanding dog clipper blade numbers is one of the simplest ways to transform your grooming results. The right blade gives you control, comfort, and a polished finish for every coat type — but only if your tools are cared for. That’s why knowing how to oil clipper blades is just as important as choosing the right size. Together, they ensure smoother grooms, longer-lasting blades, and happier dogs.

What Clipper Blade Numbers Mean

Every blade number tells you how much hair will be left after clipping. Lower numbers leave longer hair, while higher numbers cut closer to the skin. Choosing the right number helps you achieve the look you want while protecting the coat and skin underneath. The higher the number, the shorter the cut. The lower the number, the longer and fluffier the finish.

Here’s a quick guide to the most commonly used blades and their best uses:

Blade	Approxmiate Length of Coat Left	Ideal for	Best for
#3F	13mm	Long, plush finishes for breeds like Golden Retrievers or Doodles.	Long, plush finishes for Doodles, Golden Retrievers.
#4F	9mm	Neat body trims that still keep some fullness.	Tidy all-over trims with light shaping.
#5F	6mm	General body work for medium coats.	Everyday body work on medium-coated breeds.
#7F	3mm	Thicker coats that need shaping and definition.	Thick or textured coats needing definition.
#10	1.5mm	Sanitary areas, paw pads and face trimming.	Sanitary areas, paw pads, face detail.
#30	0.5mm	Used under attachment combs for precision.	Under attachment combs for precision.
#40	0.25mm	Very close clipping (e.g., surgical or hygiene areas only).	Very close work, veterinary or hygiene areas only.

Pro Tip: Start longer, then work shorter. It’s kinder to the coat — and to your nerves — especially when grooming anxious or sensitive dogs. By beginning with a longer blade or comb attachment and working shorter if needed, it reduces the chance of over-trimming. And is gentler on sensitive skin.

Why Blade Maintenance Matters as Much as Blade Choice

Even the perfect blade won’t perform well if it isn’t cared for. Even the best dog grooming blades lose their edge without proper care. Regular clipper blade oiling prevents friction, rust, and overheating. This protects both your equipment and the dogs you groom. A well-oiled blade glides smoothly, stays cool, and produces cleaner results with less effort.

A dry or unlubricated blade creates friction, heat, and drag. That means discomfort for the dog and strain for you. Regular oiling keeps the metal cool, smooth, and gliding effortlessly. This will reduce fatigue and ensure a professional finish.

How often should you oil clipper blades?

Before every groom
Every 10–15 minutes during longer sessions
After cleaning and before storage

Apply a drop of clipper oil along the teeth and sides of the moving blade while the clipper runs. Let it distribute evenly, then wipe away any excess. It takes seconds, but it makes every groom easier and every blade last longer. Avoid relying on sprays alone, they don’t replace proper lubrication.

The Groom + Kind Way

At Groom + Kind, we believe excellence is built from care — care for your tools, your craft, and the dogs you groom. Understanding your blades and maintaining them well isn’t just about performance; it’s about creating a calmer, more comfortable experience for both groomer and pet.

Explore our collection of clipper blades, oils, and blade-care essentials designed to help you work smarter, not harder. Because great grooming starts with kindness — to yourself, and to every dog on your table.