Step-by-Step Guide: How to Kasher a Microwave Easily

Do you want to ensure that your microwave is kosher? Kashing a microwave may seem like an overwhelming task, especially if you’re a beginner. But don’t worry, we’ve got you covered! In this guide, we will take you through the step-by-step process of kashering a microwave with ease. Whether you need to kasher your microwave for the first time or you’re looking for a refresher, we’ve got all the information you need right here.

Key Takeaways:

  • Learn the step-by-step process for kashering a microwave
  • Understand the kashrut guidelines and rules that apply to microwaves
  • Gather the necessary supplies before you begin the kashering process
  • Clean your microwave thoroughly to remove any traces of non-kosher food or residue
  • Identify the kasherable parts of your microwave and focus your efforts on those areas

Understanding Kashrut Guidelines for Microwaves

Before we get into the nitty-gritty of kashering a microwave, it’s essential to understand the kashrut guidelines and rules that apply to microwaves. In Judaism, kashrut refers to the set of dietary laws that govern what is considered suitable for consumption and how food must be prepared.

When it comes to microwaves, the kashrut rules are relatively straightforward. Since microwaves heat food by exciting water molecules, there is no need to worry about issues of absorption or residue. Therefore, as long as the microwave is clean and hasn’t been used to cook non-kosher food, it’s technically considered kosher to use.

However, there are a few additional guidelines to keep in mind:

  • Do not use a microwave to cook meat and dairy products at the same time, as this is considered a violation of kashrut.
  • Only use a microwave to heat up kosher food, and never use it for anything non-kosher.
  • Keep separate microwaves for meat and dairy products to avoid cross-contamination.

In addition to these guidelines, it’s worth noting that some people prefer to use a microwave with a kosher certification. This certification ensures that the microwave has been properly inspected and meets all kashrut standards. If you’re interested in using a certified kosher microwave, be sure to do your research and find one that meets your needs.

Did You Know? The first kosher microwave was developed in the late 1970s by Litton Industries, a defense contractor that had also become a leading manufacturer of microwave ovens.

Now that you have a better understanding of the kashrut guidelines for microwaves, let’s move on to the essential supplies you’ll need to gather for the kashering process.

Gathering the Necessary Supplies

microwave with kashering supplies

Before you begin the process of kashering your microwave, it’s important to gather the necessary supplies. Having these items on hand will make the process smoother and more efficient, ensuring that you are prepared to properly kasher your microwave. Here are the items you will need:

WaterUsed to purge the microwave and heat it to a high temperature.
Bowl or measuring cupUsed to hold the water for boiling and heating in the microwave.
Disposable towel or spongeUsed to clean the microwave and remove any debris or residue.
Koshering agent (optional)If you prefer to use a koshering agent, you will need to have it on hand for the kashering process.

Make sure you have all these supplies before you begin. It’s essential to avoid interruptions while kashering your microwave to maintain the continuity of the process.

Cleaning the Microwave Thoroughly

kosher microwave cleaning

Before you start the kashering process, you need to clean your microwave thoroughly. Non-kosher food or residue can compromise the integrity of the kashering process and render it invalid. Follow the steps below to ensure your microwave is spotlessly clean and ready for koshering:

  1. First, remove any debris or loose particles from inside the microwave. You can use a dry paper towel or cloth for this step.
  2. Next, prepare a cleaning solution using equal parts water and white vinegar. Pour the mixture into a microwave-safe bowl and place it inside the microwave.
  3. Turn on the microwave and heat the solution on high for about five minutes. The steam from the solution will loosen any grime or grease inside the microwave.
  4. After the timer goes off, let the solution sit inside the microwave for a few minutes. This will allow it to cool down and give it time to work its magic.
  5. Remove the bowl from the microwave and use a damp cloth to wipe down the interior of the microwave. Make sure to clean all surfaces, including the corners and the door seal.
  6. Rinse the cloth in water and wring it out, then wipe down the interior again to remove any leftover vinegar residues.
  7. Finally, wipe the exterior of the microwave with a clean, damp cloth.

It’s crucial to dry the interior and exterior of the microwave thoroughly to avoid any moisture build-up, which can lead to mold growth. You can use a dry paper towel or cloth to wipe down the microwave.

Note: If you have a self-cleaning oven, you can use it to clean your microwave. Place a bowl of water inside the microwave and run the self-cleaning cycle. This will generate steam, which will help loosen any grime or grease inside the microwave. After the cycle is complete, wipe the interior with a damp cloth as described above.

With a clean microwave, you’re now ready to start the kashering process!

Understanding the Kasherable Parts of the Microwave

Microwave diagram with highlighted Kasherable parts

Before you start the kashering process, it’s important to understand which parts of the microwave can be kashered.

The Kasherable parts of the microwave are the ones that come in contact with the food. These include:

Kasherable PartsNot Kasherable Parts
Turntable support and roller ringMicrowave ceiling and walls
Microwave wallsControl panel and keypad
Microwave ceilingLight bulb
Microwave floorExhaust fan

It’s important to remember that non-kasherable parts cannot be kashered and must be thoroughly cleaned instead.

Knowing which parts can be kashered will help you focus your efforts on the right areas and ensure that your microwave is properly cleaned according to kosher guidelines.

Step 1 – Boiling Water to Purge the Microwave

step by step kashering for a microwave

The first step in kashering a microwave is purging it with boiling water. This process helps remove any non-kosher substances that may be present.

To begin, fill a bowl or container with water and place it inside the microwave. It’s important to note that the water should cover the entire surface of the bowl or container.

1Place a bowl or container of water in the microwave
2Set the microwave to the highest power setting and run it for 5-10 minutes
3Use oven mitts to remove the bowl or container from the microwave

After running the microwave for 5-10 minutes, let it sit for a few minutes to allow any steam to dissipate. Use oven mitts to carefully remove the bowl or container from the microwave, as it will be hot.

This step helps ensure that all non-kosher elements are removed from the microwave before moving on to the next step.

Step 2 – Heating the Microwave to a High Temperature

step-by-step kashering for a microwave

After purging the microwave with boiling water, the next step is to heat it to a high temperature. This step is crucial in ensuring that any remaining non-kosher elements are eliminated. It’s essential to check the manufacturer’s instructions to determine the maximum safe temperature for your microwave. Most microwaves reach temperatures between 160°F and 190°F.

Fill a microwave-safe bowl with water and place it in the center of the microwave. You can add a wooden utensil to the bowl to ensure the water boils evenly. Turn the microwave on high and heat it for 5-10 minutes, or until the water boils and steam covers the inside of the microwave. If your microwave doesn’t have an automatic turntable, pause the heating process about halfway through to rotate the bowl.

Once the microwave has reached the desired temperature, turn it off and keep the door closed. Avoid opening the door immediately to allow the steam to continue to circulate and disinfect the microwave. Let the microwave rest for at least one hour to cool down and complete the kashering process.

Step 3 – Letting the Microwave Rest

step by step kashering for a microwave

After heating the microwave to a high temperature, it’s important to let it rest for at least 24 hours before using it again. This crucial step allows the heat to continue its work on any remaining non-kosher substances and ensures that the microwave is fully cleansed.

During the resting period, avoid placing any food or utensils inside the microwave. Instead, leave the door closed and let it sit undisturbed.

It’s worth noting that the resting period can vary depending on your specific kashering needs. If you are following the guidance of a rabbi or other authority, be sure to follow their recommended resting time.

In the meantime, take this opportunity to clean any accessories that cannot be kashered, such as the microwave’s control panel or exterior. Use a damp cloth and mild soap to wipe away any dirt or grime, being careful not to get any water inside the microwave.

Table: Recommended Microwave Resting Periods

Kashering MethodRecommended Resting Period
Regular Kashering (i.e., for Passover)24 Hours
Double Kashering (i.e., for meat and dairy)72 Hours

This table details the recommended resting periods for regular kashering and double kashering. Double kashering is the process of koshering a microwave that has been used for both meat and dairy products, and requires a longer resting period to ensure full cleansing.

Remember, the resting period is a crucial step in the kashering process. Don’t rush this step or try to use the microwave before it’s fully cleansed. Patience is key to ensuring a successful kashering experience.

Step 4 – Cleaning and Inspecting the Turntable and Accessories

Step by step kashering for a microwave

When kashering a microwave, it’s important to pay special attention to the turntable and other accessories. These items can be more difficult to clean and may require extra care to ensure they meet kosher standards. Here’s a step-by-step guide to cleaning and inspecting these parts:

  1. Remove the turntable and accessories from the microwave. Take care not to damage these items during removal.
  2. Wash the turntable and accessories with soap and water. Use a mild soap and a soft cloth to clean these items thoroughly. Take care not to scratch or damage the surfaces, as this can make them harder to clean in the future. Rinse the items well and dry them completely with a clean towel.
  3. Inspect the turntable and accessories for cracks, chips, or other damage. Discard any items that are damaged or have cracks, as these can be difficult to clean and may harbor non-kosher particles. Replace damaged items with new, kosher-certified pieces.
  4. If the turntable and accessories have been used with non-kosher food, consider immerse them in boiling water. Place the items in a pot of boiling water and leave them for several minutes. This can help further clean the items and ensure they meet kosher standards.

Once you have finished cleaning and inspecting the turntable and accessories, you can move on to the next step in the kashering process. By taking the time to clean and inspect these items properly, you can ensure that your microwave is completely kosher and ready for use.

Step 5 – Final Cleaning and Maintenance Tips

step by step kashering for a microwave

Once you have successfully kashered your microwave, it’s important to maintain its cleanliness and kosher status. Here are some final cleaning and maintenance tips to help you keep your microwave in top shape:

  • Wipe down the interior regularly: To prevent any build-up of non-kosher substances, make sure to wipe down the inside of your microwave after every use. Use a damp cloth or paper towel with soap and water, and dry it with a clean cloth to avoid any water damage.
  • Replace accessories as needed: If your microwave has any removable parts that cannot be kashered, such as charcoal filters or grease screens, check the manufacturer’s instructions for replacement guidelines. Make sure to purchase kosher-certified replacements if necessary.
  • Have your microwave inspected regularly: It’s a good idea to have your microwave inspected by a kosher-certified professional on a regular basis, especially if you use it frequently for cooking.

By following these simple steps, you can ensure that your microwave remains kosher and in good condition for all your cooking needs.

Microwave Kashrut Certification: What You Need to Know

kosher microwave certification

If you rely on a microwave to prepare your meals according to kosher guidelines, it may be worth considering purchasing a certified kosher microwave. A certified kosher microwave has been tested and approved by a reputable kosher certification agency, ensuring that it meets all the necessary standards for kosher cooking.

When a microwave receives kosher certification, it means that the materials and production processes used in its construction are free of any non-kosher substances. This includes everything from the plastic used in the microwave’s construction to the electronic components inside.

Benefits of Using a Certified Kosher Microwave

There are several benefits to using a certified kosher microwave, including:

  • Peace of mind: If you follow kosher guidelines, knowing that your microwave is certified kosher can give you peace of mind that you’re cooking in a manner consistent with your beliefs and values.
  • Convenience: A certified kosher microwave saves you the time and effort required to kasher a non-certified microwave before every use.
  • Versatility: A kosher microwave can be used for both dairy and meat dishes, as long as it has separate dishes and utensils for each.
  • Community approval: In some communities, using a certified kosher microwave is a sign of commitment to observing kosher guidelines and can help you connect with like-minded individuals.

Finding the Right Certified Kosher Microwave

When looking for a certified kosher microwave, it’s important to choose one that has been certified by a reputable agency. Some well-known kosher certification agencies include the Orthodox Union, Star-K, and the OK Kosher Certification.

You should also consider your needs when choosing a certified kosher microwave. Do you need a large capacity for family meals, or do you primarily use your microwave for basic reheating? Do you prefer a certain color or style? By evaluating your needs, you can choose the best certified kosher microwave for you.

Keep in mind that a certified kosher microwave may be more expensive than a non-certified one. However, for those who value the convenience and peace of mind that a certified kosher microwave provides, the investment can be well worth it.


Congratulations, you have successfully learned how to kasher a microwave! By following the step-by-step guide and understanding the kashrut guidelines, you can now use your microwave with confidence in your kosher kitchen.

Remember, cleaning your microwave thoroughly before and after use is crucial to maintain its kosher status. Also, make sure to inspect the kasherable parts of your microwave and keep them clean and free from any non-kosher residue.

Consider a Certified Kosher Microwave

If you use a microwave frequently in your kosher cooking, you may want to consider investing in a certified kosher microwave. These microwaves have undergone rigorous testing and certification processes to ensure they meet kosher standards.

When selecting a certified kosher microwave, look for a reliable certification agency, such as the Orthodox Union (OU), which is widely recognized and respected in the kosher industry. With a certified kosher microwave, you can enjoy the convenience of microwave cooking with peace of mind.

Thank you for reading our comprehensive guide on how to kasher a microwave. Happy cooking!


How often should I kasher my microwave?

It is recommended to kasher your microwave whenever it comes into contact with non-kosher food or if you are transitioning from a non-kosher to kosher kitchen.

Can I use the same method to kasher any type of microwave?

Yes, the kashering process is generally the same for all types of microwaves. However, it’s always best to refer to your microwave’s manufacturer guidelines for any specific instructions.

Is it necessary to clean the microwave before kashering it?

Yes, it is crucial to clean your microwave thoroughly before starting the kashering process. This ensures that all non-kosher residue is removed, making it easier to achieve a kosher status.

Can I kasher the entire microwave, including the control panel?

No, the control panel and electrical components should not be immersed in water or brought into direct contact with heat. It is best to clean these surfaces according to the manufacturer’s instructions to maintain their functionality.

How long should I let my microwave rest after the kashering process?

It is recommended to let your microwave rest for at least 24 hours after the kashering process is complete. This allows time for any remaining non-kosher elements to dissipate.

Can I use my kashered microwave for both meat and dairy products?

Yes, once a microwave has been properly kashered, it can be used for both meat and dairy products. However, it is important to ensure that the microwave is thoroughly cleaned between uses to avoid any cross-contamination.

Can I use commercial microwave cleaning sprays for kashering?

No, it is recommended to avoid using commercial microwave cleaning sprays during the kashering process. These sprays may contain non-kosher ingredients or chemicals that could interfere with the kashering process.

Can I kasher my microwave if it has a non-removable turntable?

Yes, you can still kasher your microwave even if it has a non-removable turntable. Clean the turntable thoroughly and make sure it is made of a material that can be kashered, such as glass or ceramic.

Is it necessary to cover food when reheating it in a kashered microwave?

It is not necessary to cover food when reheating it in a kashered microwave. However, covering food can help retain moisture and prevent splattering, so it is a personal preference.

Can I use my kashered microwave on Shabbat?

It is important to consult with your local rabbi or halachic authority regarding the use of a microwave on Shabbat. There may be specific guidelines or restrictions based on your own religious observances.