Sharpen a Dull Knife on the Edge of a Mug

Shawna Bailey
by Shawna Bailey
2 Materials
2 Minutes
Dull knives are not only hard to use, but they're dangerous, too, because they're so hard to control. I actually found this handy sharpening hack on a different website, and it got me wondering if it worked. So, I got out a mug and tried sharpening my knife on the bottom of it -- and it worked!

I couldn’t believe it! Dull knives are so dangerous, this little tip could be a real finger saver.
Here’s my dull knife barely able to cut through a carrot. Step 1: Get a Mug
I used a mug, but the truth is almost any ceramic piece will do, as long as it has a rough, unglazed edge. Step 2: Flip It Upside Down
I flipped the cup to find the unglazed edge. The unglazed edge is the part on the bottom that is rough, because there is no glaze on it. There is usually some area left unglazed to prevent the piece from sticking to the surface it sits on inside the kiln. Step 3: Run the Edge of Blade Over the Mug Edge
I held the blade firmly just above the handle and ran the blade in a slight arc motion. The best angle to sharpen these type of kitchen knives is between 20 and 30 degrees from the mug. Unless your blade is chipped, it only takes a few passes to become sharp again. Step 4: Repeat on the Second Side
Once one side seemed sharp enough, I simply did the same thing on the other side, to really create that fine, razor-blade edge.
It came out beautifully sharp! This hack is particularly useful for camping, or any similar situation where you find yourself with a dull knife and no sharpener.
How much smoother -- and safer -- is that!
Suggested materials:
  • A ceremic mug
  • A dull knife
Frequently asked questions
Have a question about this project?
3 of 4 questions
  • Kathy Harris Kathy Harris on Jul 28, 2016
    Great thing to know! Thanks! I LOVE your blue cup and would like to know where to find it please.😊

  • Kwe523 Kwe523 on Jul 29, 2016
    Is this a ceramic knife in the pics?

  • Ellen Ellen on Jun 13, 2017
    That knife hold is what's dangerous!

Join the conversation
2 of 43 comments
  • Cookiecutter Cookiecutter on Jun 13, 2017
    I have used the flat electric coils that lift up on my daughter's electric stove top. Works good!

  • Nonie Nonie on Jun 13, 2017
    I have/had plenty of dull knives and saw this and tried it ---- GOLLY! It worked! So I continued to sharpen others and scissors! Now I'm not the only sharp thing in the house LOL. Sorry I couldn't resist. Thanks for the tip.