Every LEGO collector and builder has been here. You are holding a brick, plate, slope, or Technic piece and you need to know what it is. Maybe you are rebuilding a set and a piece is missing. Maybe you are sorting a bulk purchase and you want to catalog everything. Maybe you found something unusual and want to know if it is rare. Whatever the reason, the question is always the same: what is this part and what is its number?
The traditional answer has been to browse through BrickLink's catalog until you find a visual match. That works if you know which category to look in and you have twenty minutes to spare. For most people, it does not work at all. You end up scrolling through hundreds of similar-looking parts, second-guessing whether you are looking at a 1x2 plate with rail or a 1x2 plate with groove, and eventually giving up or guessing.
There are now better options. I have tested four different methods for looking up LEGO parts by image, and the differences in speed and accuracy are significant. Here is an honest comparison based on real-world testing with common parts, unusual parts, and deliberately difficult pieces.
This is the tool I built because the other options were not good enough. The GameSetBrick Brick Scanner uses AI image recognition trained on over 60,000 LEGO elements - parts, minifigures, and complete sets. You point your phone camera at a piece, the AI analyzes the image, and it returns the part identification with the BrickLink part number, name, and category.
Speed: Two to five seconds from camera capture to identification. No manual searching, no category browsing, no part number entry.
Coverage: Over 60,000 parts in the database. That covers virtually every standard LEGO element produced in recent decades plus most older parts. Printed and decorated elements are included, which is where other tools often fail.
Accuracy: In my testing across 200 random parts from different eras and themes, the scanner correctly identified the part on the first attempt about 85% of the time. For the remaining 15%, it provided a close match that was easy to refine manually. The most common misses were parts with very subtle geometric differences - like distinguishing a 1x2 plate with center stud from a 1x2 jumper plate when photographed from certain angles.
Access: Free. No download required. Works in any browser at gamesetbrick.com. The camera permission request happens once and then you are set for every future scan.
Best for: Quick identification when you are sorting, shopping, or building. This is the method I use daily because it is the fastest path from "what is this piece" to an answer.
BrickLink's catalog is the gold standard for LEGO part data. Every part LEGO has ever produced is cataloged there with photos, color information, set appearances, and pricing. The problem is that using it to identify a part by appearance means browsing through categories manually.
Speed: Five to twenty minutes per part, depending on how quickly you can narrow down the category. If you already know it is a Technic pin or a specific plate type, you can find it in a few minutes. If you are staring at an unusual bracket or connector with no idea what category it belongs to, prepare for a long scroll.
Coverage: Complete. Every LEGO part ever made, in every color, from every set. BrickLink's database is unmatched in depth and accuracy. This is the reference that every other tool validates against.
Accuracy: 100% - if you find the right part. The challenge is getting there. The catalog does not have image search. You are browsing thumbnails visually and comparing them to the piece in your hand. Misidentification happens when two parts look similar in photos but differ in subtle ways like stud count, height, or connector type.
Access: Free to browse. Requires a BrickLink account for some features.
Best for: Definitive identification when you need to be absolutely certain. Also the best option for extremely obscure or prototype parts that might not be in AI databases yet. I use BrickLink as the final confirmation when the scanner gives me a result I want to double-check.
Rebrickable offers an AI part recognition tool called RebrickNet. It was one of the earlier attempts to solve the LEGO part identification problem with machine learning, and it deserves credit for pioneering the approach. However, its database has limitations.
Speed: About five to ten seconds for the AI processing, plus time to upload a photo.
Coverage: Approximately 300 of the most common part types. This covers the basics - standard bricks, plates, slopes, and common Technic parts - but it misses specialized elements, printed parts, newer molds, and many vintage parts. If you are trying to identify something unusual, RebrickNet probably will not have it.
Accuracy: Reasonable for the parts it does cover. Within its limited database, it generally returns the correct part or a close match. The issue is not accuracy within its scope but the scope itself. If the part is not in the training data, you get no result or a wrong result.
Access: Free through the Rebrickable website. Requires a Rebrickable account.
Best for: Quick identification of common, standard parts when you do not want to use a phone camera. The upload-based approach works from a desktop where you already have photos of the parts.
Google Lens is built into the Google app and Google Photos on most phones. It does general object recognition and visual search. Some people try to use it for LEGO part identification because it is already on their phone. Here is the reality.
Speed: Two to three seconds for the image analysis.
Coverage: It searches the entire web for visual matches, so in theory everything is covered. In practice, the results are a mess. Google Lens does not understand that you are looking for a specific LEGO part number. It returns a mix of shopping results, blog posts, and visually similar images that may or may not be the same piece.
Accuracy: Poor for specific LEGO part identification. In my testing, Google Lens correctly identified the specific part number about 15% of the time. The rest of the results were either generic ("LEGO brick"), wrong ("LEGO 2x4 brick" when you scanned a 2x3), or irrelevant shopping links. It is not trained for this task and it shows.
Access: Free on any Android phone and through the Google app on iOS.
Best for: Honestly, not much when it comes to LEGO parts. It can sometimes help identify a complete set from a box image, but for individual parts it is more frustrating than helpful. You will spend more time filtering bad results than you would have spent just browsing BrickLink.
I ran a controlled test with 20 LEGO parts of varying difficulty - five common bricks, five specialized Technic elements, five printed or decorated pieces, and five unusual or vintage parts. I timed each method from start to correct identification.
GameSetBrick Brick Scanner: Average 4.2 seconds per part. Correctly identified 17 of 20 on the first attempt. The three misses were all vintage parts from the 1980s that required a second scan from a different angle - two of which succeeded on the second try.
BrickLink catalog browse: Average 8.6 minutes per part. Correctly identified 20 of 20. Perfect accuracy but the time investment is brutal. The fastest identification took 2 minutes (a standard 2x4 brick). The slowest took 22 minutes (a small Technic connector I could not find the right category for).
Rebrickable RebrickNet: Average 12 seconds per part. Correctly identified 8 of 20. All five common bricks were identified correctly. Three of five Technic elements were identified. Zero printed parts were identified. Zero vintage parts were identified. The coverage gap is the clear weakness.
Google Lens: Average 45 seconds per part (including time to evaluate results). Correctly identified 3 of 20. All three were extremely common parts (2x4 brick, 2x2 plate, 1x1 round plate) where Google's web search happened to surface the right BrickLink page.
The winner on combined speed and accuracy is not close. The Brick Scanner in GameSetBrick handles the vast majority of parts in under five seconds. For the rare case where it misses, BrickLink's manual catalog is the reliable backup.
No AI tool is perfect. When the scanner does not return a confident match, here is how I fall back to manual identification efficiently:
- Measure the stud dimensions first. Count the studs in each direction. A 2x4 plate narrows your BrickLink search to a specific category immediately. This is the single most useful narrowing step.
- Note the height. Is it a plate (one-third height), a brick (standard height), or a tile (plate height, no studs on top)? This eliminates two-thirds of the options right away.
- Check for part numbers. Many LEGO parts have a tiny molded number on the inside or underside. This is the actual mold number and you can search it directly on BrickLink. Not all parts have them, but when they do, it is an instant answer.
- Look for connection points. Clips, bars, pins, axle holes, and ball joints all narrow the category. A 1x2 plate with a clip on the side is a very specific part.
- Use color as a filter. If you know the part category, BrickLink lets you filter by color. A dark red 1x2 tile might appear in only a handful of sets, which helps confirm you have the right part.
The best workflow is scanner first, manual second. The scanner handles 85% or more of identifications instantly. The manual process handles the remaining edge cases with confidence. Together, there is no LEGO part you cannot identify.
Identifying parts is not just an academic exercise. Here are the real situations where fast, accurate part lookup saves time and money:
Bulk lot sorting. When you buy a bulk lot of LEGO by the pound, you need to know what you have. The scanner turns a multi-hour sorting session into something manageable. Scan the unusual pieces, catalog the valuable ones, and sort the commons by type. I wrote about using the scanner for finding rare parts in bulk lots if you want the detailed workflow.
Replacement parts. Missing a piece from a set you are building? Identify it with the scanner, then order the exact replacement from BrickLink. No more guessing at part numbers or accidentally ordering the wrong variant.
MOC building. When you are designing a custom build and need a specific connection or angle, being able to quickly identify parts in your collection means you spend more time building and less time searching.
Reselling. If you break down sets to sell individual parts, accurate identification is essential. Listing a part with the wrong BrickLink number means returns, bad reviews, and wasted time. The scanner ensures you list the right part every time.
Whatever your reason for needing to identify a LEGO part, the fastest path is an image scan. Point your camera, get your answer, and move on to the thing you actually care about - building, collecting, or selling. Check out the bulk scan mode if you need to identify many parts in a single session.
Try it. Open gamesetbrick.com on your phone, tap the Brick Scanner, point it at a piece. Free, no download.