How to Sharpen a Santoku Knife with a Whetstone
By WÜSTHOF - Official Online Store | Published: 2026-10-30
Category: How-to Guides
Learn how to sharpen your Santoku knife using a whetstone. Step-by-step guide for a razor-sharp edge, including tips for hollow edge models.
Quick answer
Use a combination whetstone (400/2000 grit) to sharpen your Santoku knife. Start with the coarse side to repair the edge, then switch to the fine side for a polished, razor-sharp finish.
Why a whetstone works best for Santoku knives
Santoku knives have a thinner, harder blade than many Western chef's knives, which makes them more prone to chipping if sharpened on a steel or electric sharpener. A whetstone gives you precise control over the angle and pressure, preserving the delicate edge geometry.
If your Santoku has a hollow edge (granton edge), the indentations reduce friction when slicing, but they also mean you must avoid pressing too hard near the edge during sharpening. The stone will naturally follow the blade's curve if you maintain a consistent angle.
Choosing the right grit for your Santoku
A combination whetstone like the WÜSTHOF 400/2000 gives you both a coarse side (400 grit) for setting a new edge or repairing damage, and a fine side (2000 grit) for honing and polishing. For routine maintenance, you may only need the fine side.
If your Santoku is very dull or has nicks, start on the coarse side. For a knife that still cuts but feels less sharp, skip the coarse side and go straight to the fine side.
Step-by-step sharpening process
- Soak the whetstone: Submerge the stone in water for 10-15 minutes until bubbles stop rising. Place it on a damp cloth or non-slip mat to prevent sliding. A dry stone will clog with metal filings and scratch the blade. Always soak before use.
- Find the correct angle: Hold the Santoku at a 15-degree angle to the stone. For a hollow edge Santoku, angle the blade so the edge contacts the stone, not the hollow indentations. If you see the hollow edge touching the stone, you are too steep. Adjust until only the cutting edge makes contact.
- Start with the coarse side (400 grit): Place the heel of the blade on the stone and push the blade away from you in a sweeping motion, covering the entire edge. Apply light pressure. Repeat 10-15 strokes per side. Do not rock the blade. Keep the angle constant. A common mistake is applying too much pressure, which can chip the thin Santoku edge.
- Switch to the fine side (2000 grit): Rinse the stone and flip to the fine side. Repeat the same sweeping motion with lighter pressure. Do 10-15 strokes per side. The edge should feel smooth, not rough. If the edge still feels rough, it is not ready. Continue with the fine side until the burr is gone and the edge feels polished.
- Test the sharpness: Wipe the blade clean and try slicing a piece of paper or a tomato. A sharp Santoku should cut cleanly without tearing or crushing. If it drags, repeat the fine side strokes. If it still fails, go back to the coarse side and re-establish the edge.
- Clean and store the stone: Rinse the stone thoroughly and let it air dry completely before storing. Do not store it wet, as it can crack or grow mold. A dry, clean stone lasts longer and gives consistent results next time.
Product facts
- Classic 7" Hollow Edge Santoku: The Santoku's sharp blade allows anything from regular to wafer-thin cuts, making it indispensable for mincing, chopping, and preparing fish and meat. A properly sharpened Santoku will glide through vegetables and boneless proteins without tearing, preserving the texture of your ingredients.
Classic 7" Hollow Edge Santoku - Whetstone J 400 / 2000: The WÜSTHOF 400/2000 Whetstone has a coarse side to smooth off unevenness and a fine side to hone and sharpen the knife. Using both sides in sequence lets you first correct any edge damage and then refine the edge to a razor finish, all with one stone.
Whetstone J 400 / 2000
