HOWTO reproduce a key from a distant, angled photo

Sneakey is a project from Benjamin Laxton, Kai Wang, and Stefan Savage at the UCSD vision lab that has shown that it is possible to duplicate keys from photos taken at a distance and/or an angle. They've published a paper and are offering to release their code if there is "sufficient interest."

The access control provided by a physical lock is based on the assumption that the information content of the corresponding key is private --- that duplication should require either possession of the key or a priori knowledge of how it was cut. However, the ever-increasing capabilities and prevalence of digital imaging technologies present a fundamental challenge to this privacy assumption. Using modest imaging equipment and standard computer vision algorithms, we demonstrate the effectiveness of physical key teleduplication --- extracting a key's complete and precise bitting code at a distance via optical decoding and then cutting precise duplicates. We describe our prototype system, Sneakey, and evaluate its effectiveness, in both laboratory and real-world settings, using the most popular residential key types in the U.S.
Sneakey (Thanks, Fipi Lele!)


  1. It isn’t even that much work. When I was in college fifty years ago everybody in the dorm knew that if you locked yourself out of your room you borrowed a key to some other room to get in. It seemed there were only about ten different keys for the whole building. More recently I locked myself out of a Ford van. My buddy brought out a box of Ford keys and the second one he tried opened the door. It didn’t even look the same as my key!

  2. You could extend this system to have a parametric model that spits out the right shaped model when based on the bitting code… but then it would be too easy ;)

    At Hacking at Random ’09 I was 3D printing keys with our RepRap. Ray was presenting on how they created a model, also from a photograph. You can now make keys that are used for Dutch and German police handcuffs.
    We were also able to fool someone with the coins they had at HAR. There was a white ’10 euro’ in value coin. For more details, see:

  3. My grandma had a safe-deposit box where the key came with a brass sheet-metal sheath that snugly covered the teeth.

  4. Oh goody, a new and semi-legit reason to hassle people with cameras. Cameras as burglar tools.

    Officer: Give me that camera! You were taking pictures of keys. You’re under arrest.

    Me: huh?

    (muffled sounds of something being dragged)

  5. Major yawn. Some locksmiths have solved car lockouts by duplicating the key lying on the car seat “by eye”. This just replaces skill with a bit more technical assistance.

  6. Well, here’s another great idea. And the point of this is to make clear how easy it would be to copy a key of one were so inclined so please be careful? Or, here’s another way to illegally enter a house if you’re not brave enough to kick in a door?

    While I think it’s interesting, I wouldn’t say any good could come from this.

  7. Wasn’t this done some time ago and, I think, posted here? I seem to recall something about somebody climbing on top of a building, aiming a camera down at another building, through a window, and photographic keys on a desk, then going home and making that key.

    Also, Dave “Bear” Edwards from can do this by sight- give him a car key, and he can tell you what make, what model(s), give it back to you, and then hand you a copy he cut from memory next week.

  8. On a semi-related note, I once accidentally stole a bike (that looked a lot like mine (I gave it right back)). The guy had the same brand lock as me (kryptonite u-bolt)…

    Anyway, I just shoved my cylindrical, internally-toothed key into the lock, and gently tried to turn it while vibrating my hand, and BAM, lock open.

    Keys are NOT meant to be an absolute security device. They’re just a component of a good security policy.

  9. @ knodi: those barrel locked kryptonite locks are of a notoriously poor design. i don’t think it’s a good example. they can be opened with a bic pen.

  10. The pictured key appears to be a kw-1, used for one of the three most common locks in the USA and certainly the most common key by far in my area.

    It’s not necessary to have very high technology to duplicate one of these from a photo; nearly anyone handy with a file should be able to do it. They aren’t very precise locks (as evidenced by how easy they are to bump). You can get a bump key for $3 US online.

    On the other hand, as HERSHMIRE has noted, locks are to keep honest people out, and the Kwikset is a reasonably priced and reasonably durable device.

    This technique for dealing with angled photos should work with more difficult keys, though. You could probably even get it to work with side-pitted keys if you can get a snap of the pitted side.

  11. Ths s nthr nw nr ntrstng. S s Cry jst tryng t prmt th crmnlztn f phtgrphy?

    What the hell was the point of devoweling this?

    Just curious…

  12. I agree with #23 anon. Working at a place that cuts keys, there are about 5 blanks that fit at least 80% of residential locks. You could freehand the cutter to the image, or print and transfer the image of the original onto the blank.

    Locks are of limited utility under most circumstances; often, they just slow an intruder down.

  13. wow thats so great, are you going to show how to avoid leaving DNA at a rape, or maybe the cool latest way to hotwire a car!! So helpful!

  14. Reminds me of the Diebold voting machine ‘hack’. The Diebold site had an actual picture of a voting machine master key on their site. Some students bought some blanks that looked similar and used a dremel tool (they didn’t have any professional key cutting tools) to make their own master keys. Something like 2 of the 3 keys they made worked.

  15. i have been cutting them from sight only for about ten years it is not that hard. You certainly don’t need any fancy program to do it. useless waste of space is all this story is.

  16. This is pretty standard photogrammetry. In the old days you did it by taping the photo to your drafting board and reversing the perspective. If you can find two parallel lines and something to set the scale you are in.

    This technique also showed up during the Diebold voting machine controversy. Apparently, Diebold posted a photo of their default voting machine key online and one hacker actually made a key from the posted image, and it worked. It was written up at Freedom to Tinker, see

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