Can You Boil Water In The Microwave?


There are certainly a lot of ways to boil water but some can take longer than others. I’ve known some kettles to seemingly take forever to get to boiling point and if you’re using a saucepan on the stove, you’d better grab some reading material because you’re going to be waiting for a while!

But since most of us have a microwave in the kitchen, it leaves you wondering whether you can boil water in the microwave. 

You can boil water in the microwave and it’ll usually take around three minutes. However, you need to be careful when doing this as there are risks involved.

If you want to know how to safely and successfully boil water in the microwave then you’re in the right place. This guide will tell you everything you need to know. 

Should You Boil Water In The Microwave?

Boiling water in the microwave can seem like an easy and convenient idea. That said, this appliance isn’t primarily designed for heating water so a lot of people wonder whether they’re doing the right thing using it this way. 

Where you can, I would recommend using your kettle or the stove for boiling water. However, I’m aware that there may be times this isn’t possible and your microwave is the only option. 

It is possible to use your microwave to boil water but there are some risks involved that you should be aware of.

The problem is that, when boiling water in the microwave, there is a chance that the water will heat way above the normal boiling point. And this isn’t something that you have a great deal of control of with a microwave. Your kettle will power off once the water reaches 100 degrees so there’s no risk of it overheating. 

Why would hotter temperatures be dangerous, I hear you ask? Well this is largely to do with uneven heating where steam can build up under cold parts of the water. The result of this could be an explosion which of course, may cause nasty injuries.

So, if you are going to use your microwave to boil water, it is essential to do this correctly and that means taking the time to stop and stir the liquid. Doing this should get rid of any concern of explosions. 

Are There Risks Involved In Boiling Water In The Microwave?

There are two main risks involved with boiling water in the microwave. Provided you heat the water gradually and follow the tips I’ll provide later in this guide, you should be OK. However, it’s really important to educate yourself on the potential risks as this will better help you to mitigate them. 

For starters, there is a risk of getting burned. Your microwave won’t only hear up the water but the container you have put it in as well. There is a risk of sustaining a burn by touching this hot container and of course, you also risk spilling the boiling water onto your skin which is not nice; believe me, I’ve done it and it’s hugely painful! But, we learn from our mistakes.

As well as the potential risks to yourself, there is also the risk of what is known as superheating. This happens when water is heated past its normal boiling point of 100 degrees celsius. Due to a lack of bubbles in the water when it’s in the microwave, there is a risk that pressure will be released once you stir the liquid, thus causing an explosion.

While you might think that this is unlikely to happen, it’s worth noting that these issues are incredibly common and not something that should be overlooked. You have very little control over what is happening to the water while it is in the microwave so it pays to be incredibly careful. 

How Does A Microwave Boil Water?

When you put water into the microwave, the molecules in the liquid are heated by the appliance. Compared to other methods, this happens a lot more quickly. You’ll likely even notice that water heats up much faster in the microwave than other food items. 

This is where superheating becomes a risk. When superheating occurs, any vapour from the water will turn into bubbles. While this might happen before with other heating methods, it tends to happen only after the water is disturbed; for example, when you stir it or move the container. This is when that explosion I mentioned could potentially happen. So, it’s worth exercising extreme caution when taking the water out of the microwave.

If you heat water in the microwave for too long then superheating becomes even more of a danger. Generally speaking, you should not put water in the microwave for more than two to three minutes. However, this will vary between appliances and I’ll go into more detail on this later on. 

That said, it is possible to use your microwave to boil water safely and conveniently; when it is done properly. The microwave will cause uneven heating but one of the best ways to avoid this is to only boil small amounts of liquid at any one time.

The microwave uses electromagnetic waves which increase friction between the molecules in the water. The result of this is the production of heat. But this heat is produced randomly and that’s where the problem lies.

How To Properly Heat Water In The Microwave

It goes without saying by now that there are risks to using a microwave for boiling water. Again, I’ll stress that this shouldn’t be your go to method but when you have no other choice, the following steps will ensure the safest possible process. 

  1. Make sure that you use a container that’s safe to put in the microwave. Things like glass and ceramic are fine but you should NEVER use any type of metal.

  2. Add your water to the container but do not cover it with a lid or anything else. 

  3. You can use an implement, such as a wooden chopstick, to check whether superheating has occurred. Simply place this into the water before switching on the microwave. 

  4. Set the microwave to run for one minute and allow it to work its magic. 

  5. Open the microwave door and gently tap the chopstick to see if the water has superheated. Doing this will disturb the water just enough to let out any bubbles and heat without causing an explosion. 

  6. Carefully take the container out of the microwave using protective gloves or a towel.

  7. If the water is not hot enough, you can return it to the microwave for another 30 seconds and check it again. But be careful not to exceed any more than three minutes. 

How Long Does It Take To Boil Water In The Microwave?

Normally, it shouldn’t take any longer than one to three minutes to heat water in the microwave. But the length of time will be affected by the type of microwave you are using and this is in relation to its power. 

Microwave power is given in watts. The lower the wattage, the longer it will take to get the water to boiling point. More powerful microwaves will heat the water extremely quickly so you’ll need to be extra careful.

Here are some guidelines on how long to boil your water in the microwave. 

Microwave Power

Length Of Time

600 watts

4 minutes

700 watts

3 minutes

800 watts

2.5 minutes

1000 watts

2 minutes

1200 watts

1 minute

Things To Keep In Mind When Boiling Water In The Microwave

As well as considering the right length of time for boiling water in the microwave, there are plenty of other things you’ll need to do if you want this process to be as safe as possible. 

When it comes to time, you might not need as long as I have detailed in the table above. Similarly, you may need to give the water another 30 second blast if it isn’t hot enough. Much of this will be to do with how much water you are using but it’s always best to stop and check every 30 to 60 seconds. For microwaves that may take three minutes, you should never set the timer and just leave it to run. 

  • If you have older containers or cups then these are ideal for heating water in the microwave. That’s because the cracks and scratches on these containers will help to create bubbles making it a much safer option. 

  • It’s imperative to use a stick, like the wooden chopstick we discussed earlier, to check if the water is superheated. This will allow you to let the water spill out inside the microwave rather than picking it up and sustaining a nasty burn. 

  • Make sure that you always wear protective gear when handling boiling water out of the microwave. It might seem a little over the top but when you get a burn, you’ll realise exactly why I’m advising this.  

Conclusion

Boiling water on the stove or in the kettle isn’t always the quickest option. That said, these are definitely the safest ways to boil water. 

But if you’re in a rush, you might want to use your microwave but you’ve likely asked can you boil water in the microwave?

You can boil water in the microwave but there are some serious risks involved. There is the potential for the water to become superheated and potentially explode which could leave you with some painful burns. 

If you must boil water in the microwave, follow the tips in this guide to make sure that you remain as safe as possible.