What it means
This refers to the blade thickness just above the cutting edge. This is where it is decided whether the knife goes through cleanly or wedges.
Knowledge: Geometry
Why geometry matters more than marketing
When a knife feels like it cuts through butter, the reason is often less about the steel and more about geometry: angle, blade thickness behind the edge, and grind type determine how the knife cuts rather than just scratches.
Key rule: "Sharp" is the edge. "Cutting-eager" is the geometry behind it.
Angle: per side vs. inclusive angle
Angle specifications are often confusing. Some state the angle per side, others the total angle (including both sides).
| Angle (per side) | Total angle | Feel | Good use |
|---|---|---|---|
| 12–15° | 24–30° | very fine, very direct | Precision cooking, clean technique, soft boards |
| 15–17° | 30–34° | strongly cutting-eager | Gyuto/Santoku, good all-round for many |
| 18–20° | 36–40° | robust, forgiving | Everyday chef's knife, family kitchen, rougher use |
| 20–22° | 40–44° | stable, less laser-like | Outdoor/utility, very demanding tasks |
Thin behind the edge: the everyday secret
How it feels
A thin knife needs less pressure, stays straighter in the cut line and splits onions less.
The tradeoff
Very thin is efficient but more sensitive to lateral forces. Technique and board become more important.
Grind type: V, convex, hollow (and why you notice)
Flat / V-grind
Simple, precise, easy to reproduce. Many kitchen knives end up here.
Typical: very good sharpness, food release depends on the blade face.
Convex
More material behind the edge, but without a thick wedge. Good mix of stability and glide.
Typical: stable, glides well, feels smooth.
Hollow grind
Very thin at the edge, often very sharp, but can be more delicate depending on use.
Typical: aggressive bite, faster material removal when sharpening.
Microbevel: the tiny edge that adds real stability
A microbevel is a tiny secondary bevel on the edge at a slightly higher angle. It can reduce chipping and stabilize the edge in daily use without completely widening the geometry.
- 1
Grind the base: set your normal angle and build a clean edge.
- 2
Raise the angle slightly: really just a few degrees, then a few very light passes per side.
- 3
Deburr: fine alternating strokes, then optionally a leather strop.
If a knife feels sharp but loses its edge quickly during cutting, the cause is often a bad burr or an edge that is too fine (too acute) for daily use. A microbevel is then often the pragmatic fix.
Food release, wedging and why potatoes stick
- Blade height and flank shape: wide blades release food better when the flank is not too flat.
- Wedging effect: thick knives push food apart. This is noticeable with hard carrots.
- Distal taper: when the blade gets thinner towards the tip, the tip feels noticeably more precise.
Geometry and technique must match
Why does my knife feel dull even though it shaves?+
Often it is not the edge but wedging: the blade is too thick behind the edge. You notice this especially with onions and carrots.
Why do I get chips even though the steel is top-notch?+
Too acute an angle, geometry too thin for your use, or lateral forces during cutting (twisting in the cut, pushing sideways). Solution: adjust technique or add a microbevel / slightly larger angle.
Which technique is safest for thin knives?+
Push cut and controlled strokes without lateral pressure. The knife works forward/downward instead of being twisted.