How to Sharpen a Kitchen Knife

Dull knives are a bummer. They're in the in-law's cabin. They're in your home kitchen. They crush tomatoes instead of slicing them. They slow you down, make prep feel harder than it should be, and quietly steal the pleasure out of cooking.

Sharp knives fix all of that. Here's how to get there.

What You'll Need

Before anything else, decide which method fits your kitchen and your patience level. There are three main tools for sharpening a kitchen knife:

• A whetstone (sharpening stone) — the best result, highest skill floor, most satisfying
• A pull-through sharpener — fast and easy, but removes more metal and leaves a rougher edge
• A honing rod — not actually sharpening (more on this below), but essential for edge maintenance between sharpenings

Most home cooks benefit most from learning the whetstone. It gives you control, produces a better edge, and extends the life of your knives over time. That's what this guide focuses on.

First: Understand the Difference Between Sharpening and Honing

This trips people up constantly. They're not the same thing.

Sharpening removes metal from the blade to create a new edge. You do this when the knife is genuinely dull, when it slides off a tomato instead of cutting it, or when it struggles through an onion.

Honing realigns the edge you already have. A honing rod (the long steel that often comes with knife sets) doesn't remove (much) metal, it just straightens out the microscopic folds that develop from regular cutting use. Think of it like combing the edge back into alignment.

Hone regularly. Sharpen as needed — usually every few months for home cooks who cook 4–5 nights a week.

How to Sharpen a Knife on a Whetstone: Step by Step

Step 1: Choose Your Stone

Whetstones come in different grits, just like sandpaper. Lower numbers are coarser and remove metal faster. Higher numbers are finer and polish the edge.

• 120–400 grit — for repairing chips, broken tips, or very dull edges
• 800–1000 grit — the workhorse grit for most regular sharpening
• 2000–3000 grit — for refining and smoothing after the coarser work
• 6000+ grit — for polishing to a fine, razor edge

If you're just starting out, a combination stone with 1000 on one side and 3000–6000 on the other covers most situations. The King 1000/6000 is a solid, well-tested option.

If you want to just skip to tools that make the work faster and more enjoyable consider the new hard resin diamond "stones" from Grind at Vivront.

Step 2: Soak or Splash Your Stone

Most traditional whetstones need water or a few minutes of soaking before use, check the manufacturer's guidance. The water floats away the metal particles (called swarf) as you work, keeping the surface cutting cleanly. Diamond and ceramic stones typically don't need soaking.

Step 3: Find Your Angle

This is the part that often intimidates people most. It doesn't need to.

For most Western knives (Wüsthof, Henckels, etc.) aim for about 15–20 degrees per side. For most Japanese knives, 10–15 degrees. If the existing edge is already established, try to match it rather than fight it.

A simple way to find the angle: lay the knife flat on the stone (that's zero degrees), then lift the spine until a matchbook would just barely fit underneath. That's roughly 15 degrees. Hold that consistently and you're in good shape.

Another way to match the angle of the knife is to use bright light. Shine it on the blade laying flat on the stone. Note the small shadow under the cutting edge. Slowly tilt the knife toward the cutting edge until the shadow is gone. You'll have matched the angle on the knife. 

Step 4: Build the Bevel — Start on One Side

Place the blade on the stone at your chosen angle. Using light to moderate pressure, push the blade across the stone with the spine leading the motion, tip to heel.

Repeat this motion on the same side until you can feel a slight rough edge or curl, often called a burr, forming on the opposite side of the blade. Run your thumb gently over (not along) the edge from spine to cutting edge to feel for it. When you feel it consistently along the whole length, tip to heel, that side is done with that stone grit.

This is the core of sharpening. The burr tells you you've worked the metal to the edge.

Step 5: Flip and Repeat on the Other Side

Flip the knife and repeat the same motion on the other side. You'll feel the burr shift to the other side. Work until the burr shifts to the other side from the tip to the heel.

Step 6: Move to a Finer Grit

If you have a finer grit stone, repeat the process there. You're not rebuilding the edge — you're refining and smoothing the scratches you created on the coarser abrasive. Typically you'll use lighter pressure at this stage. And, it'll require fewer passes.

Step 7: Remove the Burr

After sharpening, a microscopic burr (curl) remains. Stropping of some sort can remove it.

A strop is typically a piece of leather, sometimes with a compound on it for a little extra abrasion. Hold the blade at a steeper angle than you sharpened at. Alternate sides, light pressure, for only as many passes as are needed to remove the burr.

No strop? A few alternating light passes on a piece of cardboard or the back of a leather belt can work in a pinch.

Step 8: Test the Edge

The paper test: hold a sheet of printer paper and slice downward through it. A sharp knife cuts cleanly and smoothly. A dull one tears or catches. If you use a paper towel, sharp knife cuts and one with leftover burr will leave traces of paper towel stuck in it. 

The tomato test: set a ripe tomato on the cutting board and let the weight of the knife alone start the cut. A sharp knife will begin to bite in immediately without pressing down.

How to Use a Honing Rod (Between Sharpenings)

Make this a habit. A few passes on a honing rod before or after cooking keeps your edge straightener and performing longer. Entry level honing:

1. Set the rod horizontally on the counter
2. Place the tip of the blade near the end of the rod at the knife's bevel angle
3. Draw the blade across the hone, tip to heel
4. Use light pressure until the edge is straighter

Note: a smooth steel rod hones. A rod with diamond or ceramic coating actually sharpens slightly. That is, it removes a little metal. Both are useful, but they're doing different things.

Want something easy to use before a hone? Consider a Stick by Sharpow. Developed at Vivront from thousands of interactions with cooks about honing. 

How to Sharpen a Serrated Knife

Yes, you can tune a serrated knife with a hone on the flat side of the knife. To sharpen serrated knives, the process is different. Each individual serration needs to be addressed separately using a tapered rod or a specially shaped stone. Most home cooks find this tedious enough that professional sharpening makes more sense for serrated blades. We sharpen serrated knives at our Edina shop and via mail-in service.

How Often Should You Sharpen Kitchen Knives?

It depends on how often you cook and what you're cutting. Kind of like how often you might need new shoes. A reasonable starting point for most home cooks:

• Hone: before or after every few uses
• Sharpen: every 2–4 months if you cook 4–5 nights a week
• Sharpen sooner if you're cutting on hard surfaces (glass, ceramic, titanium, stone), storing knives loose in a drawer, or running them through a dishwasher regularly. All of these activities accelerate edge wear

The best indicator is the knife itself. When the tomato test fails, or the knife just bounces off the food, it's time.

Common Whetstone Sharpening Mistakes

• Inconsistent angle — the most common problem. The blade needs to stay at the same/similar angle through the whole pass. Practice slowly before adding speed.
• Too much pressure — more pressure doesn't mean faster sharpening. It means uneven metal removal and a rougher edge. Let the stone do the work.
• Not checking for a burr — if you're not building a burr, you haven't reached the edge yet. Keep going on that side.
• Skipping the strop — the edge feels sharp off the stone but still has metal fragments clinging to it. Stropping makes a real difference in the final result.
• Sharpening a stone-cold dull knife on a fine grit — start coarser. A 6000 grit stone isn't going to rescue a knife that needs a 1000 grit first.

When to Get Your Knives Professionally Sharpened

Some situations call for a pro:

• Chipped or broken tips that need more metal removed and a profile rebuilt
• Knives that have been sharpened at inconsistent angles and profiles over time and need a reset
• Single-bevel Japanese knives that require specific technique
• When you just want it done well without the learning curve

Vivront sharpens at our Edina shop at 50th & France. same day if you drop off before 2PM. We also offer mail-in sharpening nationwide with prepaid shipping both ways. Most people are surprised how much better their knives feel after a professional sharpen and how long they stay that way with regular honing.

FAQ

What's the best angle to sharpen a kitchen knife?

15–20 degrees for most Western knives. 10–15 degrees for most Japanese knives. If your knife already has an established bevel, match it rather than fight it. Use the high intensity light trick to find the bevel angle on each knife as mentioned above. 

Can I sharpen a knife without a whetstone?

Yes, a pull-through gadget, an electric sharpener, or even the unglazed ceramic bottom of a mug can "sharpen" a blade in a pinch. None produce as good a result as a whetstone with skill, but they work. We wrote more about the downsides of pull-through sharpeners here if you want the full picture.

How do I know if my knife is sharp enough?

The paper test and the tomato test (described above) are the most practical. Some sharpeners use a BESS scale for precision measurement. Here's how that works.

Do knife sharpeners wear out?

Yes. Pull-through sharpeners lose their abrasive over time. Typically, the cheaper the faster. Whetstones wear unevenly and need flattening for crisp cutting. More on this here.

What's the difference between honing and sharpening?

Sharpening removes metal to create a new edge. Honing realigns the existing edge without removing metal. You need both... full explanation here.

Can you sharpen a serrated knife?

Yes, but it takes more time and different tools. Each serration can be addressed individually. Most home cooks opt for professional sharpening on serrated blades.

Happy cooking!

Keep Your Kitchen Sharp

Vivront sharpens kitchen knives professionally — the same way a Japanese knife shop would, not the way a pull-through gadget does.

Mail your knives to us → We ship a padded kit to your door, you send your knives in, we return them sharp. Works anywhere in the US.

Set up a sharpening subscription → Sharp knives on a schedule, without thinking about it.

In the Twin Cities? Drop off at our Edina shop (same-day if you're in by 2pm), or check the schedule for our mobile sharpening truck.

Know a school that could use a fundraiser? Our PTO sharpening kit program lets parents send in knives and a percentage comes back to the school. Easy sell, useful product.