Discolored LEGO is one of the main problems for LEGO enthusiasts. With the years, and especially if the LEGO has been exposed to direct sunlight, the pieces will start to discolor. This is mostly true for white, and grey pieces. In this post, I am putting together all the information I found online about the topic.

To restore discolored LEGO, the most common solution is to put them in a bucket with Hydrogen Peroxide and let that work for a few hours or days. In most cases, it is recommended to place that on the sun, which helps with the reaction. After that, the pieces will go back to their initial color.

There are a few things to keep in mind with the process, so be sure to read on.

Tips to restoring discolored LEGO with Hydrogen Peroxide

As I just mentioned, the most common solution that people use successfully is placing your discolored LEGO pieces in a bucket with Hydrogen Peroxide and leaving that sit for a few days in the sun or under a UV lamp.

This solution actually comes from some enthusiasts for retro computers that wanted to bring the color back to the old computers. They came up with a system they named “Retr0bright“. In this case, they combine the Hydrogen Peroxide with some “Oxy” laundry, which would speed up the process, working as a catalyst. Instead of days, the color would be back in just a few hours.

However, the solution most available online is without the “oxy” laundry. It takes longer, but it seems that it is much more tested with LEGO pieces. So, let’s have a look in more detail about the process most used, which does not involve the “oxy” laundry.

Before we proceed, though, please bear in mind that this solution works for white, and grey pieces. Blue colored bricks, which can also get discolored will actually lose a bit of color by using this technique, so be mindful of that when using this solution with blue bricks.

So, the process for white, and grey is as follows.

Step 1 – Fit all your pieces in a bucket, ideally tall and thin

So, the first step in this process is to find a container where you can fit all your pieces. If you have a lot of pieces, it might be worth doing this in more than one badge.

As I say in the title, the recommendation is to get a container that is tall and thin. This is because the LEGO pieces tend to float, which we don’t want. The best solution is to place something on top so they cannot go up. So, the thinner the container, the less “top” there is, so the easier it is to cover and avoid floating pieces.

Step 2 – Fill the bucket with Hydrogen Peroxide, ideally concentration 3%

After you have placed all the pieces, it is time to fill the container with the Hydrogen Peroxide. Now, before you go and do that, be sure to read the instructions. Most people recommend using a 3% concentration so if you have or have bought Hydrogen Peroxide with higher concentration, I would recommend that you dilute it in water.

Once you have the right concentration and you have read the instructions to make sure you are wearing the appropriate protection (such as gloves and goggles), fill the container up until it covers all the pieces you have.

Step 3 – Fit a large piece on the top

The next step is to fit a large piece on the top, that matches as well as possible the size of the container. With this, we will avoid smaller pieces floating on the container.

If they were to float and some part of the piece stayed outside, you would end up with a part of the piece with the right color and another part of the piece with the wrong color. Not something you want.

Step 4 – Add a heavy object (such as a stone) on top of the large piece

The last step, to avoid any pieces floating, is to place a heavy object on top of the large piece. This will ensure that also the large piece stays submerged, pushing down all the other pieces below it.

A small rock is a great option because it will not react with the Hydrogen Peroxide. If you don’t have a stone, though, make sure that whatever you are using will not be affected by or affect the Hydrogen Peroxide.

Step 5 – Place the bucket outside if it is sunny or, alternatively, under a UV lamp

The next step is to place the bucket outside or if where you live tends to be always cloudy (hello UK), under a UV light. This will kickstart the reaction so that the Hydrogen Peroxide starts working. Without this step, most resources ensure that this will not work, but some do claim that this worked even without this step.

Step 6 – Check every few hours to make sure the liquid is still covering all the pieces

The next step is to check the bucket every few hours (if possible) to make sure the liquid still covers all the pieces. The solution evaporates, so you will probably need to add a bit more every once in a while.

Step 7 – Once the color is back to what it was, rinse and dry

The amount of time you need until you can take it out will vary depending on the amount of sun you get and how discolored your pieces were. What everyone recommends is to check against a sample of a new piece and take the pieces out from the solution once you are satisfied with how similar it is to that color.

Once this is done, you only need to rinse the pieces and let them dry. It is actually quite easy to do and, even though it is long, it just needs to be sitting there for a long time, but it is not much time consuming for you.

Can I damage the LEGO pieces by leaving them too long?

Yes, you can damage in the sense that the color will whiten too much. This is not the case for white pieces, but the brighter the color, the more risk there is. Therefore, keep an eye every few hours to make sure no damage is being done, especially for non-white pieces.

What about the other colors?

Other colors that are not white, grey, or blue do not have so many problems with decoloring as these three colors do. For what I have been able to find online, there are mixed opinions about them. Some people claim that the colors whiten a bit, as it is the case of the blue, but others would say that the colors stay the same.

The longer you leave them inside the liquid, the more risk there is of them becoming whiter. My personal advice would be to avoid placing any other colors in the solution if possible.

What about pieces with stickers?

There are also mixed opinions about placing stickers inside the solution, although most of the opinions I have been able to find state (and show) that there is no problem with placing the stickers inside the solution and that they come out without any visible damage.

My personal advice, in this case, having seen a few videos of people showing it, would be to do it.

Final words

And with this, we have arrived at the end of this post. If you want to restore your LEGO because you would like to resell them, be sure to check our post “A Guide To Making Money Selling Used LEGOS”. In it, we explain all you need to know about making money online by selling used LEGOS.

To avoid the discoloring of stored LEGOS, check our post “The Best Storage Tips For Keeping LEGO Like New”. There, we explain all the steps to follow to keep your LEGO looking like the first day, including some advice to avoid the decoloring we have discussed in this post.

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If you are interested, here is a link to the entire Lego section found on Amazon.