How to Sharpen a Knife Without a Sharpener

By
Melissa Breyer
Melissa Breyer
Editorial Director
  • Hunter College
  • F.I.T., State University of New York
  • Cornell University
Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others.
our editorial process
Melissa Breyer
Updated October 11, 2018
CC BY 2.0. Didriks/flickr

A kitchen hack to make MacGyver proud.

Maybe one of the best lessons a cook can learn about kitchen tools is knife care, yet it's a skill that goes woefully neglected. I'm speaking from firsthand experience here – I've got beautiful knives that slice and dice and performs feats of derring-do, but do I have a knife-sharpening set-up at home? No. In my striving for a simple kitchen, I stubbornly resist having too many single-purpose gadgets, even when common sense suggests otherwise. I can tell you, prepping food with dull knives is like the cook's equivalent of performing delicate surgery wearing mittens. I know that a sharpening rig is not the worst eco-sin, but until my obstinance eases (and I have more storage room) I praise the mighty hack.

If your knife can easily slice through a sheet of paper when doing a Zorro move with it, it's sharp enough. Likewise, if it can slip through the skin of a tomato or the flesh of an onion, it's sharp enough. A dull knife, on the other hand, will offer resistance and can slip of that which you are cutting, which can lead to cut fingers. This we want to avoid.

So if you're stuck with a dull knife and no sharpener, either in your own kitchen or maybe you're guest-cooking at the home of a friend, here's a trick. You don't need a knife sharpener, just grab a plate ... or bowl or a mug. The kind folks at ACS have got the science to show us how: