Are Duplo Building Blocks Dishwasher Safe? (How To Clean Them)

Last updated on September 14th, 2022 at 08:57 pm

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Last updated on September 14th, 2022 at 08:57 pm

The Lego Company is the maker of the Duplo Building Blocks that are geared towards preschool aged children. Duplos have been around for over 40 years but there are still many questions that people have about them. As each new generation starts to play with Duplos there are questions that come up about them. 

A common question that many people have is about cleaning them and specifically if you can wash them in the dishwasher or not. 

According to the Lego Brand Company they discourage the use of a washing machine or a dishwasher for cleaning Duplos because they are likely to get deformed at those higher temperatures. You can wash it in hot water in a sink as that water will typically be 100-110 degrees rather than the 130-140 of a dishwasher. 

At approximately 130 degrees Fahrenheit Duplos can start to get deformed which is why it is not recommended to wash them in a dishwasher as you will be likely to bend the Duplos or deform them which makes putting them together far more difficult if not even impossible. 

It is also not a good idea to try and use an oven, hairdryer or microwave to dry the blocks either. This added heat will also push the temperature of the blocks dangerously close to the deforming point which ultimately will ruin the block.

The cleaning and disinfection of your Duplo Building Blocks is still possible but, it should be done with a different method which will not possibly affect the quality of the block by using these high temperature appliances that many people have become accustomed to using.

Can You Put Duplos In A Washing Machine?

Now that we know that you shouldn’t put Duplos in a dishwasher the next thing that many people look to is a washing machine. Since there are different temperature cycles on the washing machine you can obviously keep your Duplos from becoming deformed but should you wash them in a washer? 

Although you can wash Duplos in a washer if you have it on a cold wash setting that won’t do a whole lot to sanitize them as you really need to have hot water for that which means that you should not wash Duplos in a washer either. 

If you have some Duplos that have become extremely dirty from being used outside in the dirt, sand, etc. or are caked with other materials then putting them in a washer on the cold setting might work to get some of the gunk off of them, however, most of the time it is better to simply wash them in a sink full of hot water and soap. 

Safe Cleaning Of A Duplo Building Block

Cleaning your different Duplo Blocks is not complicated in any way and is honestly pretty easy to do. If you follow this process it will keep you from possibly damaging your Duplos while trying to clean them. 

It is always a good idea to clean your blocks by hand, using tap water at a temperature of no more than 104 degrees. You can also use a soft cloth or sponge to clean the blocks by hand which makes getting in the crevices a bit easier. 

A dish soap can be added to the tap water to ensure your Duplos are effectively being cleaned. After cleaning the blocks be sure and rinse them with fresh water and lay them out to dry. I would suggest laying them out on a clean dish drying mat or even a dish towel. 

To disinfect the Duplo building blocks it is recommended to use household rubbing alcohol, but of course this should only be done by an adult. To do this process just wipe the blocks down with a clean cloth and a small amount of rubbing alcohol.

How Do You Sanitize Blocks That Are Used Consistently?

When Duplo blocks are used in a large quantity and very often in places such as a preschool, daycare, or camp, it is not recommended to clean them with anything other than warm mild soapy water. Due to specific chemicals in other cleaning products they could potentially degrade the components of the block and make them unusable.

A possible alternative is to divide the blocks in half or quarters (depending on the amount of Duplos that you have) and rotate the blocks in and out of use every few days with proper recommended cleaning in between each use. 

Due to the benefits of the blocks pertaining to building fine motor skills, not using them would be a difficult choice based on the center’s current needs. Duplo blocks were developed for younger children with education, imagination and other skills in mind so having less blocks available but never having no blocks because of cleaning is ideal in most scenarios. 

Other Ways To Clean Your Duplos

Some alternatives to deep cleaning are based on the dirtiness of the blocks as some may just be dusty. One method is to just soak them in warm soapy water in a tub and then coming back later and using an old toothbrush or cloth to further wipe them off. 

Some blocks may just occasionally need to be rinsed. Placing them in a colander and shuffling them around while rinsing them with clear tap water may be all that is needed (of course depending on how they have been used). 

An individual may find an assortment of Duplo building blocks at a garage sale or thrift store so obviously under those circumstances, the blocks would need to be cleaned and sanitized for safety.

This would require possibly soaking them overnight in warm/hot mild soapy water, scrubbing all of the blocks with a toothbrush and then finally sanitizing with rubbing alcohol. You should then give the Duplos a second rinse and allow the blocks to dry fully by placing them on a towel for approximately 24 hours or more. This will ensure they are fully dry.

It is never recommended to submerge any electrical components or battery components into water if those are included with your Duplo sets as this has the potential to damage the parts and create rust and corrosion. The parts may seem fine after submersion but the safety risk with small children is not worth it. 

Duplo building blocks are all waterproof just not all the components that come with them. These blocks are also easier to clean than standard Lego’s as they are designed to be twice the size for younger children to learn and grow which makes cleaning all of the holes and studs far easier. 

Again, it is not advisable to use a dishwasher, washing machine or even bleach for cleaning as this will affect the structure and quality of the building block and could possibly make them entirely worthless. 


Duplo building blocks were designed for a younger target group from 1 ½ years old to 5 years old. These blocks are normally found in individual homes, daycare centers and even in day camps. This makes cleaning and sanitizing the blocks important especially since children in that age range are not known for their cleanliness. 

Everyone carries germs and by following the recommended cleaning and sanitizing guidelines germs and bacteria can be reduced/eliminated allowing for safe play.

Using warm water that is not over 104 degrees, mild detergent, rinsing, letting fully dry and then sanitizing with household rubbing alcohol is the perfect way to make sure your Duplos are clean and also sanitized. 

Remember heat from a dishwasher and washing machine will compromise the block’s structure so don’t use them unless you are willing to risk possible destroying the Duplos entirely. 

Last updated on September 14th, 2022 at 08:57 pm

Matthew R

Hi, My name is Matt and I am all about toys! When trying to find accurate information online about toys I was finding it difficult so I decided to make this site.

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