Knife Sharpening Angle Guide
Find the correct sharpening angle for kitchen, hunting, pocket, and Japanese knives.
Calculate the edge bevel and spine height for your whetstone.
Knife sharpening angle is the angle between the blade and the sharpening surface. The angle determines how sharp and how durable the edge will be.
Lower angle = sharper but more fragile Higher angle = less sharp but more durable
Recommended angles by knife type:
| Knife Type | Angle Per Side | Total Included Angle |
|---|---|---|
| Japanese kitchen knives (single bevel) | 10–15° | 10–15° total |
| Japanese kitchen knives (double bevel) | 15° | 30° total |
| Western kitchen knives (chef’s knife) | 17–20° | 34–40° total |
| Pocket / folding knives | 20–25° | 40–50° total |
| Hunting / outdoor knives | 22–25° | 44–50° total |
| Tactical / combat knives | 25–30° | 50–60° total |
| Axes and hatchets | 25–30° | 50–60° total |
| Scissors | 45° (single edge) | — |
| Straight razors | 7° | 14° total |
| Filet / boning knives | 12–15° | 24–30° total |
How to set the angle without a guide (spine height method):
Place the knife flat on the whetstone. Lift the spine to create the target angle. Use this formula to find how high to lift the spine:
Spine Height (mm) = Blade Width (mm) × sin(angle°)
Sine, not tangent. Blade width is measured from the edge to the spine along the blade itself, so it is the hypotenuse of the triangle you make with the stone, not the base. Tangent overstates the lift by about 6% at 20° and 15% at 30°.
For a 45 mm wide blade at 20°:
45 × sin(20°) = 45 × 0.342 = 15.4 mm
Stack coins under the spine until it reaches that height:
- 1 US quarter ≈ 1.75 mm thick
- 9 quarters ≈ 15.8 mm, which is about right for a 20° edge on a standard chef’s knife
Sharpening progression (grit sequence):
| Stone Grit | Purpose |
|---|---|
| 120–400 | Reprofiling and removing chips. Skip it if the edge is just dull |
| 600–800 | Setting the new bevel |
| 1,000–2,000 | Refining the edge |
| 3,000–6,000 | Polishing the edge |
| 8,000+ | Mirror finish, straight razors |
How many strokes per side?
- Start with the same number of strokes on each side (e.g., 10 per side)
- Test with paper. A sharp knife slices it cleanly rather than tearing
- Finish with 5 alternating light strokes per side
- Strop on leather to align the very edge of the burr
Maintenance vs reprofiling:
If a knife is just dull (not chipped), start at 1,000 grit and work up. If there are chips or the edge needs to be reset, start at 400 grit. A honing steel realigns the edge between full sharpenings, and it removes almost no metal. Use it before each cooking session, not instead of sharpening.
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