Hair Clipper Blade Sizes in mm — Full Size Chart #3F to #40 (Wahl, Andis, Oster)
Every clipper blade size in mm: #3F (13mm) to #40 (0.25mm). Instant lookup chart for Wahl, Andis & Oster A5 blades, taper blades, and guard combs. Free printable PDF — updated 2026.
This clipper blade size chart covers every standard blade number from #3F to #40, with cutting lengths in millimeters and inches, compatibility notes for Wahl, Andis, and Oster clippers, and recommended uses for barbers, pet groomers, and livestock professionals. Whether you need to know how short a #40 blade cuts or which size leaves the most coat, this chart has the answer.
Once you know the blade size you need, check our blade compatibility guide to confirm which blades fit your specific clipper brand and model.
A5 Detachable Blade Size Chart
A5 blades use an industry-standard snap-on system compatible with most professional clippers from Andis, Oster, Wahl KM series, and many others. The blade number indicates the cutting length — higher numbers mean shorter cuts. See our full compatibility guide for a complete list of which A5 clippers accept these blades.
| Blade # | Cut Length | Best For |
|---|---|---|
| #3F / #3FC | 13mm (1/2") | Longest A5 cut. Body clipping for horses, long pet trims |
| #4F / #4FC | 9.5mm (3/8") | Medium-length pet grooming, body work |
| #5F / #5FC | 6.3mm (1/4") | General pet grooming, popular all-purpose size |
| #7F / #7FC | 3.2mm (1/8") | Short pet trims, face and feet work, show grooming |
| #10 | 1.5mm (1/16") | Very short trim. Pre-surgical prep, poodle faces/feet |
| #15 | 1.2mm | Surgical prep, very close trimming |
| #30 | 0.5mm | Surgical close. Under guard combs, setting lines |
| #40 | 0.25mm | Closest cut available. Surgical prep only |
What Does "F" and "FC" Mean?
"F" stands for finish cut — blades with closely spaced teeth that leave a smooth, even finish. "FC" means finish cut as well (the terms are interchangeable across brands). Skip-tooth blades (without the F designation) have wider-spaced teeth for faster cutting through thick or matted coats, but leave a rougher finish.
Hair Clipper Blade Sizes for Barbers
Professional barber clipper blades use a different sizing system than A5 pet blades. Standard taper blades adjust from closed (approximately 0.5mm) to open (approximately 2.5mm) using the clipper's lever. For more precise lengths, barbers use numbered guide combs over a standard blade.
T-blades and U-blades are specialized trimmer blades designed for outlines, fades, and detail work. T-blades (like our Model 125) have a wider, exposed cutting edge for precise lines, while U-blades (like our Model 730) have rounded corners for safer skin contact.
Ceramic vs Steel: Does Blade Material Affect Cut Length?
No — ceramic and steel blades of the same size number cut to the same length. The difference is in performance: ceramic blades stay sharp approximately 5x longer and generate 75% less heat during operation. This makes ceramic ideal for busy salons and groomers who use their clippers all day. For a detailed breakdown, read our ceramic vs steel comparison guide.
How to Choose the Right Blade Size
Consider three factors when selecting a blade size:
- Desired hair/coat length: Match the blade number to your target length using the chart above.
- Coat condition: Matted or thick coats may require a shorter blade first, then a longer blade for the final pass.
- Application: Surgical prep requires #30 or #40. General pet grooming typically uses #5F or #7F. Barber fades use adjustable taper blades with guide combs.
Blade Maintenance Tips
Regardless of size, all clipper blades perform better with proper maintenance:
- Clean and oil blades after every use
- Use blade wash or spray coolant during extended sessions
- Store blades in a dry, protective case
- Sharpen or replace blades when cutting performance drops — a dull blade pulls hair and generates excess heat. See our complete sharpening guide for step-by-step instructions.
At SUMTHIN, we manufacture A5 detachable blades in all standard sizes (#3F through #40) using MIM powder metallurgy for consistent hardness and edge retention. Our ceramic moving blades are available as drop-in replacements for any steel blade. Browse our full blade catalog, learn more about our clipper blade manufacturing capabilities, or request a quote.
Related Guides
- Blade Compatibility Table — Interactive lookup: find which SUMTHIN blades fit your specific clipper brand and model.
- Clipper Blade Compatibility Guide — Detailed explanation of A5 universal, brand-specific, and regional blade systems.
- Ceramic vs Steel Clipper Blades — Compare heat, edge life, cost, and which material fits your workflow.
- How to Sharpen Clipper Blades — Professional sharpening techniques and when to replace instead.
Frequently Asked Questions
What clipper blade size should I use for a fade?
For fades, barbers typically start with a #1 guard (3mm) on the sides and blend down to a #000 or #0000 blade (0.25-0.5mm) at the hairline. Use adjustable taper blades and gradually open/close the lever between passes. T-blades are used for the final outline and edge work.
Are all clipper blade sizes universal across brands?
A5 detachable blades (#3F through #40) are universal — they fit any A5-compatible clipper regardless of brand. However, standard taper blades and trimmer blades (T-blades, U-blades) are brand-specific and only fit certain clipper models. Check our compatibility table to verify.
What is the difference between F blades and skip-tooth blades?
F (finish cut) blades have closely spaced teeth that leave a smooth, even finish. Skip-tooth blades have wider-spaced teeth that cut through thick or matted coats faster but leave a rougher finish. For most grooming and barbering work, F blades are preferred. Skip-tooth blades are used for initial rough cuts on heavily matted pets.
What blade size is best for dog grooming?
The most popular all-purpose blade for dog grooming is the #5F (6.3mm) or #7F (3.2mm). Use #10 (1.5mm) for sanitary areas, poodle faces, and feet. Use #3F (13mm) or #4F (9.5mm) for leaving more coat length. See our dog grooming blade size chart for breed-specific recommendations.