How to Sharpen Kitchen Knives with Sandpaper

Last Updated: October 21, 2021

Sandpaper can really come in handy if you're looking for a way to sharpen a knife in a pinch. Keep reading to learn what kind of sandpaper to use, how to hold the knife against the paper, and more!

Steps

1
Get a sheet of #180 grit or #240 grit "Wet-or-Dry" silicon carbide (black) sandpaper. These can be found at any home improvement store, or even Walmart in the Paint-Wallpaper section. Sometimes these are sold in "Variety Packs" with several grits, about $3. One sheet will last for months.
2
Lay the sandpaper grit side up at the edge of a hard flat surface (table, counter top, or cutting board). This will allow you to hold the handle firmly and sharpen the entire edge.

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3
Firmly hold the knife by the handle and slide the edge across the sandpaper like you are slicing thin layers off the sandpaper. Always move the knife in that direction, "on to" the sandpaper, never backwards, in circles or straight along the edge. An angle of about 20° is best. Do not use a lot of pressure, just steady, even strokes—about like slicing a raw Irish potato.
4
Sharpen both sides of the blade the same way and the same amount. Alternate sides: Take maybe three strokes on a side, then change.
5
For knives with curved blades, raise the handle slightly while sliding the edge across the sandpaper so that you sharpen the entire length.

Community Q&A

Question

I don't want to put the sandpaper on a table or surface. What other options are there?

wikiHow Staff Editor
Staff Answer
This answer was written by one of our trained team of researchers who validated it for accuracy and comprehensiveness.

wikiHow Staff Editor

Staff Answer

You could make a sanding block instead. This would have the benefit of being moveable to any suitable surface and reusable. To make it, choose a block of wood in a suitable size. Wrap the sandpaper around the block of wood and secure with tacks or other suitable fasteners. Once made, you can run the blades over the side, untacked side of the block to sharpen them.
Question

My Pops used to sharpen knives on a mug. Is that a good idea?

wikiHow Staff Editor
Staff Answer
This answer was written by one of our trained team of researchers who validated it for accuracy and comprehensiveness.

wikiHow Staff Editor

Staff Answer

It is certainly possible to use a mug for sharpening knives. Choose a mug you don't mind using for this purpose and make sure it's unglazed. Turn the mug upside down so the base faces upward. Run the blade across the blade at an angle to sharpen it. Always run the knife in the same direction and repeat several times for the best effect.
Question

How do I sharpen serrated knives?

wikiHow Staff Editor
Staff Answer
This answer was written by one of our trained team of researchers who validated it for accuracy and comprehensiveness.

wikiHow Staff Editor

Staff Answer

It is possible to sharpen serrated knives but it must be done with extreme care to avoid breaking or ruining the knife's serrations. For help with doing this, check out the wikiHow How to Sharpen Serrated Knives.