How to clean rust off a kitchen knife

Rust is the biggest enemy of any type of metal and the biggest issue for metal knives. Many people throw their knives away as soon as they see a couple of rust spots thinking that they can’t use those any longer. But rust can be cleaned, especially when it is just starting to appear on the blade.

But before talking about the solutions, we need to address the prevention: Water and moisture are the biggest causes of rust. Never leave your steel knives in the sink for too long and avoid washing them in the dishwasher. Always dry your steel knives thoroughly after washing and you will have no rust issues for a long time. Rust is natural for metals but you will need to take care of your steel knives to avoid it as much as you can.

Now, let's talk about how to clean rust from a kitchen knife.

Image source -

1. With Baking soda

Baking soda can clean many things and luckily, rust is one of them. Cleaning rusty blades of knives with baking soda paste is a trustworthy method that has succeeded for many different types of knives. So giving it a try is the least that you can do for your rusty knife.

Image source - blog.bulletproof


All you need:

  • Water
  • Baking soda
  • Toothbrush
  • Sponge
  • Steel wool
  • Cloth



  • Clean the knife: First things first, you will need to clean your knife because dirt tends to involve in the process of rusting. Clean your knife with a cleaning product and wipe it off with a cloth. Don’t use water to wash the knife because, as we just addressed, water is the main reason that a knife’s blade rusts.
  • Make a baking soda paste: Next, you need to make the paste, which is very easy; just pour a fair amount of baking soda into a bowl and add some water or lemon juice. Stir it up until it becomes a paste.
  • Scrub the blade: Here the toothbrush comes in handy. Apply the thick paste to a toothbrush and liberally spread it across the blade. But remember that you can scrub with a toothbrush only if the rust isn’t too severe or set in.
  • Scrub with steel wool: If the blade is extremely rusty you will need something that provides more abrasion to remove it. Steel wool is a perfect candidate for that work, but remember that it can ruin your blade if you scrub too hard.
  • Scrub with a sponge: Another less damaging way to clean the blade from rust is scrubbing it with a slightly abrasive sponge.
  • Wipe the blade: And lastly, clean the baking soda off the blade with a cloth. 


2. With a potato

This might sound funny to you, but it actually works. Raw potatoes contain oxalic acid, which is able to dissolve rust from blades. This method is the easiest of them all, which is perfect if you don’t have much time to spend on cleaning rust.  

Image source - media1.fdncms


All you need:

  • Raw potato
  • Cloth



  • Stab the rusty knife into a potato.
  • Leave it like that for a few hours.
  • Remove the knife.
  • Rinse the juices off the blade.
  • Dry the blade with a clean cloth.
  • Throw the damaged potato away because it is not eatable any more.


3. With oil

Applying a light oil that will not stain or dry the metal components to a blade can remove light rust stains.

Image source - images-na.ssl

All you need:

  • Oil
  • Cloth
  • Steel wool



  • Apply the oil: Take a clean cloth and apply a thin layer of oil to the blade directly. Use a very little amount of because it can attract dust and debris.
  • The wait: Leave the knife open for two or three days. The oil will soak into the blade and it will loosen up the rust spots making them easier to remove.
  • Clean it: After three days, take a piece of steel wool and carefully remove the rust.


4. With Lemon and Salt

The combination of the acidity of the lemon with the abrasiveness of the salt can be very effective in completely removing small rust spots.

Image source -


All you need:

  • Lemon
  • Salt
  • Steel wool
  • Cloth



  • Covering: Cover the rusted areas of the blade with salt and squeeze lemon juice all over the layer of salt.
  • The wait: Let the knife soak in the mixture for about 2 hours.
  • Scrub it off: Scrub the blade with a piece of steel wool to get rid of the spots.
  • Clean it: Rinse the knife with some warm water and dry it with a clean cloth. Never leave the knife underwater for a long time; moisture can be the main reason your knives get rusty.


5. With CLR

CLR is a tested cleaner that removes calcium, lime, and most importantly, rust from any metal surface, which includes knife blades. But it also has its cons, so here are a few things that you need to remember:

  • Clean your knife in a well-ventilated area or preferably outside, and use gloves when handling CLR because it is a caustic substance.
  • Make sure to not mix CLR with other cleaners, because that can cause a dangerous reaction.
  • Also, don’t use CLR on galvanized metal, Because it might cause spotting on the zinc coating of the blade.

Image source -


All you need:

  • CLR
  • Gloves
  • Cloth
  • Warm water



  • Make the mixture: Start off by mixing a solution of half CLR and half warm water.
  • Dip the blade: Dip the blade of your knife into the mixture and make sure that the CLR doesn't touch the handle if it is not made out of metal because it will damage it.
  • Wash it: Keep the blade in CLR for exactly 2 minutes and not more. Rinse the blade immediately after with cold water.

You can use CLR at full strength without diluting it with water and rinsing it immediately after with cold water in case if stains of your blade are persistent.  

And lastly, if your knife is covered in rust to the point that nothing helps, you will have to move on and get a new one that will last you a long time without getting rusty too early. But just in case, remember that you have these methods to prevent your knives from getting too extreme rustiness that is impossible to clean.



Hello JOHN CHARLES H STEWART, We are very glad that you are enjoying your order. As for the care and sharping recommendations, our team is working on that. Thank you for your feedback.

John Charles H Stewart

Just received my knife, very pleased. I do wish the knife had come with care and sharping recommendations.

John Charles H Stewart

Leave a comment

All comments are moderated before being published