The Free LEGO Set Inventory Tracker

Between shelved sets, boxed-up sets in storage, and loose minifigures scattered across bins, it's easy to lose track of what you actually own. Collectionizer keeps your entire LEGO collection organized in one searchable inventory — so you never buy a duplicate set by accident again.

Built for how LEGO collectors actually organize

Start from a LEGO template or build your own fields — set number, theme (Star Wars, Technic, Icons, City, and more), piece count, year released, minifigures included, box and instruction condition, and whether it's built, boxed, or in storage. Add photos of the box art and the finished build.

Add sets in seconds — no manual typing

Just enter a set number and Collectionizer looks it up for you via Rebrickable, automatically pulling in the name, theme, piece count, year, and box image. Pick the right match and it's added to your inventory — or fill out the form yourself if you'd rather.

Find any set in seconds

Full-text search and field filtering let you check "do I already have this set?" while you're standing in a store aisle or browsing a secondhand listing — before you buy a duplicate.

Share your collection or keep it private

Show off your builds to other collectors, or keep your inventory completely private. You're in control.

Free to get started

Your first collection is free forever — no credit card required. Sign up now and start cataloging your sets in minutes.