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Is LEGO Sold by Weight? What That Means for You
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Sealed sets are never valued by weight. Value sits in which set it is, not how heavy the box is, and two boxes of identical weight can differ by hundreds of pounds. Price per kilo is a real thing, but only for loose mixed bricks, which is a completely different market with different buyers.
- Sealed sets are valued set by set, never by weight.
- Two identical-weight boxes can be worth vastly different amounts.
- Price per kilo applies to loose mixed bricks, and nothing else.
- Anyone offering to buy a sealed collection by weight is not valuing it.
- Loose bricks have genuine buyers, they are just different ones.
The question comes up constantly and the answer matters, because being offered a weight-based price for a sealed collection is a signal worth paying attention to.
Why weight tells you nothing about a sealed set
Weight follows piece count and packaging, not desirability. A large common set weighs a lot and is worth little per kilo. A small short-run set weighs almost nothing and can be worth several times more. Any valuation method that treats those the same is going to be wrong in both directions.
Where the price per kilo idea comes from
It is real, and it belongs to loose bricks. When LEGO is sold as a mixed bulk lot with no sets, no boxes and no sorting, weight is genuinely the only practical measure. Buyers of that material sort it, clean it and sell it on by part, and they price the raw input by the kilo because nothing else is knowable.
That has nothing to do with sealed sets, and applying it to them is either a misunderstanding or a very cheap offer wearing a method.
The three markets, kept separate
| What you have | How it is valued | Do we buy it? |
|---|---|---|
| Sealed, unopened sets | Set by set, against recent sales | Yes |
| Opened sets, complete with box | Per set, discounted for completeness risk | No |
| Built models | Per set, usually lower, and hard to move | No |
| Loose mixed bricks | By weight, by a bulk specialist | No |
| Sorted parts and minifigures | Per part, by a parts specialist | No |
If your collection is a mix of all of it
Most are. Send the whole list anyway. We will price the sealed part properly and tell you plainly which part belongs elsewhere, rather than putting a low blanket figure on everything to cover the parts we do not understand.
A warning worth taking seriously
If somebody offers to take a sealed collection at a price per kilo, they are not valuing your sets. They are pricing a category. That might be fine if your collection is genuinely mixed bulk material, and it is a poor outcome if it contains sealed sets with real individual value.
Common questions
The follow-ups this usually prompts.
What is loose LEGO worth per kilo?
It varies with how clean and sorted it is and who is buying, so any figure we gave would be a guess in somebody else’s market. A bulk specialist will tell you properly.
Why will you not buy loose bricks?
We have no route to sell them. It is a sorting and parts business and we are a sealed-sets business. We would only be guessing at the value, which is no use to you.
Are minifigures sold by weight?
No. Figures are valued individually and some are worth a great deal. If your collection includes loose figures, they are worth having looked at separately by somebody who deals in them.
Does a heavier box mean a better set?
Only in the sense that large sets weigh more. Within any weight, what decides value is which set it is and how many people want it.
How to tell which market your collection belongs to
We would rather point you at the right buyer for the other two piles than put a low blanket figure on everything to cover what we do not deal in.
- Sort into three piles: factory sealed, opened but boxed, and loose or built.
- Do not open anything to make the decision. If the seals are intact it goes in the sealed pile.
- Count the sealed pile roughly. That is the part we can price.
- Note whether the loose material is mixed bulk or sorted parts. Different specialists want each.
- Send us the sealed list, and ask us who to talk to about the rest if you are not sure.
Why the weight question keeps coming up
It is a reasonable thing to ask, and there are a few reasons it has stuck around.
- Bulk LEGO genuinely is traded by the kilo, so the phrase is out there and it is not made up.
- House clearance and general second-hand buying often does work by volume or weight, because it has to.
- It sounds objective, which is appealing when you have no idea what you have.
- A per-kilo figure is quick, and quick is attractive when a collection feels overwhelming.
The catch is that the thing making it quick is the same thing making it wrong for sealed sets. It works precisely because it ignores what each item is, and for sealed sets what each item is turns out to be all of it.
Get it valued set by set
Send a list of set numbers and rough quantities and we price each one against what it is actually selling for. One figure for the whole lot, no weighing involved.
Get a price for your collectionWritten by Peter Pilling, BuyMyBricks, 26 September 2026. LEGO® is a trademark of the LEGO Group, which does not sponsor, authorise or endorse this site. We do not buy loose bricks, built models or opened sets, and we make no valuation claims about those markets.
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