Updated: October 7, 2026
Originally published: June 10, 2020

TL;DR

Electric knife sharpeners make routine knife sharpening faster and easier, but the correct technique depends on the sharpener. Learn the stages, use the manufacturer's instructions, keep the machine dry, and avoid removing more metal than necessary.

Quick Answer

How do you use an electric knife sharpener?

Start by reading the manufacturer's instructions and identifying which sharpening stages your machine uses. Select the appropriate stage for the condition of the blade, place the knife into the correct slot, and make controlled passes according to the manufacturer's instructions. Use the same process on both sides of the blade when required.

Do not force the knife through the sharpener, use water unless the manufacturer specifically permits it, or disassemble the machine without instructions. After sharpening, clean away metal debris as directed and store the knife safely.

What Is an Electric Knife Sharpener?

An electric knife sharpener is a powered sharpening tool that uses abrasive wheels, belts, discs, or other sharpening components to restore a knife's edge.

Unlike a traditional whetstone, which requires you to control the sharpening angle manually, an electric sharpener generally guides the blade through a designated sharpening slot. Many models have multiple stages designed for different levels of sharpening and finishing.

The exact process varies by model, so the manufacturer's instructions should always take priority over general sharpening advice.

Electric Sharpener Checklist

Before sharpening a knife, check the following:

• Read the manufacturer's instructions.
• Make sure the sharpener is positioned securely on a stable surface.
• Confirm which sharpening stage you need.
• Make sure the knife is clean and free of food residue.
• Keep the sharpener and surrounding area dry unless the manufacturer specifically states otherwise.
• Inspect the blade for damage before sharpening.
• Keep your fingers away from the sharpening slots and blade edge.
• Use controlled movements rather than forcing the knife through the machine.
• Follow the manufacturer's recommended number of passes.
• Clean the sharpener after use according to its instructions.
• Protect the sharpened knife before storing or transporting it.

Getting to Know Your Electric Sharpener

An electric knife sharpener is a machine, so its controls, sharpening mechanisms, and maintenance requirements vary from one model to another.

Before using yours for the first time, take a few minutes to understand how it works.

Read the Instruction Manual

The instruction manual should be your first reference.

Look for the diagram showing the sharpener's controls, sharpening stages, blade slots, and any removable components. The manual should also explain which types of knives the machine can sharpen and which knives should not be used with it.

This matters because not every electric sharpener is designed for every blade style.

Understand the Controls

Become familiar with the power switch and any controls that determine the sharpening stage.

Some electric sharpeners use descriptions such as:

• Coarse
• Fine
• Honing
• Polishing
• Extra fine

Other models may simply label their stages as 1, 2, and 3.

Do not assume that the numbers mean the same thing on every machine. Check the manufacturer's instructions before choosing a stage.

Know Which Knives Your Sharpener Supports

Before sharpening, check whether your electric sharpener is designed for your particular knife.

Some models are intended for standard kitchen knives, while others may accommodate specialty blades. Certain knives, including some serrated, single-bevel, ceramic, or unusually shaped blades, may require a different sharpening method.

When in doubt, check the manufacturer's specifications.

Sharpening Stages and Slots

Many electric sharpeners use multiple stages. Although the exact setup varies between models, the stages generally move from more aggressive sharpening toward finer finishing.

Stage One: Coarse Sharpening

The coarse stage is generally used when a knife has lost a significant amount of sharpness or needs more substantial edge restoration.

It removes more material than the finer stages, so it should not automatically be used every time you sharpen a knife.

If your knife only needs routine maintenance, using an aggressive setting unnecessarily can remove more metal from the blade than needed.

Stage Two: Fine Sharpening or Honing

The second stage is generally intended to refine the edge created during the initial sharpening stage.

Depending on the machine, this may be described as fine sharpening or honing.

This stage can help refine the edge and prepare it for a final finishing stage when the sharpener includes one.

Stage Three: Extra-Fine or Polishing

The final stage on a multi-stage electric sharpener is generally designed to refine or polish the edge.

It is often used after a more aggressive sharpening stage and may also be suitable for routine edge maintenance, depending on the manufacturer's instructions.

Do not assume that every knife needs to pass through every stage during every sharpening session. The correct sequence depends on the knife's condition and the design of your sharpener.

How to Use an Electric Knife Sharpener

Once you understand the stages of your machine, the next step is using it correctly.

1. Clean and Inspect the Knife

Start with a clean, dry knife.

Remove any food, grease, or residue from the blade. Then inspect the edge for obvious damage.

A severely damaged, chipped, bent, or otherwise compromised blade may require professional repair rather than routine sharpening.

2. Choose the Correct Sharpening Stage

Select the stage recommended for the condition of your knife.

A knife with minor edge wear may only need a finer maintenance stage. A significantly dull knife may require a more aggressive stage first.

Always follow your sharpener's specific instructions.

3. Position the Knife Correctly

Place the blade into the appropriate sharpening slot as instructed by the manufacturer.

Do not guess the correct position or angle if the machine provides specific instructions. Some sharpeners are designed to control the sharpening angle automatically, while others require a particular technique.

4. Move the Knife Smoothly

Follow the manufacturer's recommended motion and speed.

In general, you should not force the blade through the sharpener. Controlled movement allows the abrasive mechanism to do its job without unnecessary pressure.

Do not rush.

The correct speed and number of passes depend on the machine, so use the instructions provided with your specific model rather than relying on a universal number.

5. Sharpen Both Sides When Required

If your sharpener is designed to sharpen both sides of a double-bevel knife, make sure both sides receive the appropriate treatment.

Keeping the process balanced helps maintain the intended edge geometry.

Some sharpeners handle both sides automatically, while others require you to use separate slots. Follow your model's instructions.

6. Check the Edge

After sharpening, carefully inspect the blade.

Avoid running your finger directly along the edge to check sharpness. A sharpened knife can cut you even when the edge looks clean.

Instead, use an appropriate cutting test, such as carefully slicing a piece of paper if the knife and test method are suitable.

If the knife still does not perform as expected, consult the sharpener's instructions before making additional passes.

Safety When Using an Electric Sharpener

An electric sharpener combines electricity, moving mechanical components, abrasives, and a very sharp blade. Basic safety precautions are essential.

Keep Water Away Unless the Manufacturer Says Otherwise

Unlike many traditional whetstone setups, electric sharpeners generally should not be exposed to water.

Do not pour or spray water onto an electric sharpener.

Keep liquids away from the machine and follow the manufacturer's cleaning instructions. If a particular model is specifically designed to use water or another lubricant, follow that manufacturer's directions instead.

Keep Your Hands Away From the Sharpening Mechanism

Never place your fingers near the abrasive wheels, belts, or other moving components while the machine is operating.

Hold the knife only where the manufacturer's instructions indicate.

Do Not Force the Blade

Let the machine do the work.

Excessive pressure can interfere with the sharpening process and may increase the risk of damaging the knife or using the machine incorrectly.

Keep the Blade Pointed and Controlled

Always maintain control of the knife while sharpening.

Keep your hands positioned safely and follow the movement specified by the manufacturer. Do not make sudden movements or attempt to sharpen while distracted.

Use Protective Equipment When Appropriate

Cut-resistant gloves can provide an additional layer of protection when handling knives, but they are not a substitute for safe technique.

The most important precautions are controlling the knife, keeping your hands away from moving parts, and following the sharpener's instructions.

How to Clean and Maintain an Electric Sharpener

Sharpening removes metal from a knife, so some metal particles and sharpening debris can accumulate inside the machine.

Regular cleaning helps keep the sharpener ready for its next use.

Clean the Sharpener After Use

Follow the manufacturer's cleaning instructions for your particular model.

Some machines have removable collection areas or components that make it easier to remove sharpening debris. Others may require a brush or another specific cleaning method.

Never assume that a component can be removed simply because it appears removable.

Use the Correct Cleaning Tools

If your manufacturer recommends a brush for removing debris, use the appropriate brush and carefully clean around the sharpening mechanism.

Do not put your fingers into areas where abrasive components or sharp debris may be present.

Do Not Lubricate Parts Unless Instructed

Do not automatically apply oil or lubricant to an electric sharpener.

Many models do not require lubrication, and adding a product that the manufacturer does not recommend can interfere with the machine.

If your sharpener requires maintenance lubrication, use only the product and procedure specified by the manufacturer.

Keep the Sharpener Dry and Stored Properly

After cleaning, allow the machine to remain in the condition specified by the manufacturer before storing it.

Keep it in a clean, dry location where the power cord and sharpening components will not be damaged.

Electric Sharpener vs. Whetstone and Honing Rod

An electric sharpener is convenient, but it is not the only way to maintain a kitchen knife.

The best tool depends on your knives, experience, workload, and preferred sharpening method.

For a professional cook or culinary student, having more than one method available can be useful. An electric sharpener can handle convenient sharpening, while a whetstone can provide greater control when you need it.

Practical Knife Care for Working Cooks

Sharp knives are only useful when they are also stored, transported, and handled properly.

A freshly sharpened blade should not simply be thrown loose into a drawer, bag, or backpack.

Use appropriate blade protection and keep knives separated from other equipment when transporting them between home, culinary school, a restaurant, catering job, or private-chef event.

For chefs who regularly move a knife kit between kitchens, dedicated knife guards can help protect the blade and the other equipment around it.

Your sharpening routine is only one part of good knife care. Cleaning, drying, protecting, and properly transporting your knives all contribute to keeping your tools ready for the next service.

For cooks who carry multiple knives and kitchen tools between locations, a dedicated chef knife backpack can also make transporting a complete kit more organized.

Frequently Asked Questions

How often should I use an electric knife sharpener?

There is no universal schedule. Use the sharpener when the knife's edge has become noticeably less effective, and follow the maintenance recommendations for your specific sharpener.

Routine maintenance should generally be less aggressive than restoring a very dull edge.

Can you use water with an electric knife sharpener?

Usually, you should keep water away from an electric sharpener unless the manufacturer specifically designed the machine to use water.

Always follow the instructions for your particular model.

Should I use the coarse setting every time?

No. The coarse stage is generally intended for more significant sharpening or edge restoration. Using an aggressive stage unnecessarily can remove more material from the blade than needed.

How many times should I run a knife through an electric sharpener?

There is no universal number. The recommended number of passes varies by machine, sharpening stage, knife condition, and manufacturer.

Follow the instructions for your specific sharpener instead of relying on a fixed number.

How do I know when my knife is sharp?

Use a safe cutting test rather than running your finger along the blade.

A properly sharpened knife should perform the cutting task it is designed for without requiring excessive pressure.

Can an electric sharpener replace a whetstone?

An electric sharpener can handle many routine sharpening jobs, but it does not make a whetstone unnecessary for everyone.

A whetstone gives the user more direct control over sharpening technique and edge refinement. Many serious cooks prefer having both options available.

Can I sharpen every kitchen knife with an electric sharpener?

No. Different sharpeners support different knife types.

Check the manufacturer's specifications before sharpening specialty blades, serrated knives, single-bevel knives, ceramic knives, or other unusual blade designs.

Do electric knife sharpeners damage knives?

An electric sharpener can remove metal from a blade, particularly when using a coarse stage. Incorrect use can potentially damage a knife.

Using the correct stage, following the manufacturer's instructions, and avoiding unnecessary passes can help minimize excessive material removal.

Should I oil my knife after using an electric sharpener?

If you use knife oil, follow the knife manufacturer's recommendations and apply it only after sharpening and cleaning the blade.

Do not apply knife oil directly to an electric sharpener unless the sharpener manufacturer specifically instructs you to do so.

Key Takeaways

• An electric knife sharpener can make routine sharpening faster and easier.
• Always read the instructions for your specific sharpener before using it.
• Choose the sharpening stage based on the condition of the knife.
• Do not use an aggressive sharpening stage unnecessarily.
• Never force the knife through the machine.
• Keep water away from electric sharpeners unless the manufacturer specifically allows it.
• Do not test sharpness by running your finger along the blade.
• Clean sharpening debris according to the manufacturer's instructions.
• Do not lubricate the machine unless the manufacturer recommends it.
• Protect and properly store your knives after sharpening.
• A whetstone and honing rod can still be useful alongside an electric sharpener.

About the Author

Keith Chiu is the founder of Chef Sac, a chef gear brand built for culinary professionals, culinary students, line cooks, caterers, private chefs, and serious cooks who care about how they carry their tools.

Chef Sac was created to give chefs a better way to organize, protect, and transport the tools of their craft. From knife bags and chef backpacks to aprons, knife guards, and everyday chef carry gear, Chef Sac is built for real kitchen workflows and the Culinary Mavericks who show up prepared.