The Omnimatrix is a watch-like device which attached to Ben's wrist in the first episode of the series and is the device that the series revolves around. Created by Azmuth, the Omnitrix was intended to allow beings to experience life as other species in order to bring understanding and peace in the universe, it was revealed in Ben 10: Alien Force that the Omnitrix was also a way to preserve sapient life in the galaxy if one of them ever become extinct. According to Vilgax, the Omnitrix is supposed to be the ultimate weapon. It was destroyed in The Final Battle: Part 2 in order to prevent Vilgax from taking over the Earth and replaced by the Ultimatrix. In Map of Infinity, Azmuth reveals he has is creating a third and far more superior Omnitrix. However, he refuses to give it to Ben now as it is incomplete and Ben's maturity has lately regressed considerably, making him more reckless and impatient.
In the first form that Ben encountered, the Omnitrix looked like a very big wristwatch, primarily black and grey in color, with a grey (or black) dial in the middle (like a watch face) which has a green hourglass shape (the intergalactic "peace" symbol, also on Plumber's Badges and Galvan Prime) on it. When it recalibrated, it gained a more watch-like shape, a green wristband, became smaller and sleeker, and the face dial became black and
green. The inside of the hourglass shape glows in different colors at certain moments. These colors signify the mode that the Omnitrix is presently in.
- The Omnitrix can display 8 colors, each meaning something different:
- Green: Active Mode
- Red: Recharge Mode
- Yellow: Capture Mode
- Blue: Recalibration Mode
- Purple: Controlled by Eon
- Orange: Self Destruct Mode (original Omnitrix form)
- White: Malfunctioning, but within acceptable parameters.
- Grey: Deactivated
- The Omnitrix acts as a wireless receiver for the Codon Stream. By accessing the Codon Stream, the Omnitrix rewrites the user's DNA and transforms them into one of the 1,000,910 DNA samples. In order for the host to change size, matter is created from energy or reconstituted to energy as needed.
- The Omnitrix has two known display modes:
- The mode seen in the original series provides a black silhouettes of the aliens.
- The mode in Alien Force provides dark green holograms of the aliens.
- According to Dwayne, by changing the settings on the Omnitrix, both display modes can be used in both of the Omnitrix's forms.
- The Omnitrix functions as a GPS as shown in The Final Battle: Part 1.
- The Omnitrix can alter the clothing of the wearer to better fit the alien forms. Ben lost this function in Alien Force because the Omnitrix recalibrated. Now, nanomachines break them down and store them until his transformation ends.
- The Omnitrix alters its size to fit the user's size, as shown in The Final Battle: Part 2.
- The Omnitrix can be controlled by voice, called Voice Command.
- When the user is transformed, a button with the Omnitrix symbol on it appears on the chest which can be used to switch to another form while already transformed into a specific alien. The symbol is actually the Omnitrix itself, appearing in this form because many species don't have wrists. In the original series, the Omnitrix symbol appears in random places, this is due to it not working correctly.
- When transformed, the Omnitrix can protect the host from negative influences, like possession by an Ectonurite or the mutation effect of Corrodium or Dr. Animo's mutant ray. The same effect applied to Kevin during his second mutation, as it came from the Omnitrix too.
- If someone tries to tamper with the Omnitrix against the user's will, it creates a large feedback pulse for defense.
- The Omnitrix has AI (Artificial Intelligence).
- The Omnitrix can show a database image of all aliens unlocked.
- The Omnitrix can create a hologram map, which is similar to the one in Plumber's Badges.
- The Omnitrix has a 2-way communication system with Plumber's Badges.
- The Omnitrix has a Universal Translator.
- The Omnitrix can teleport the user through Azmuth's teleportation channel.
- There is a particular method used to safely remove the Omnitrix, and Ben used it in The Final Battle: Part 1. It involves a code that the wearer of the Omnitrix uses with voice activation (Decouple Omnitrix Command Code: 000 Release Coupling 0). Ben may have known this code as he may have remembered it if he used the code to take off the Omnitrix after he was done with it sometime after the end of Ben 10.
- During transformation, all information of the alien is dumped into the user's mind. This excludes the original series (ex. Ben having to figure out the abilities of Ditto and Cannonbolt.
- When exposed to an electromagnetic interference, the Omnitrix can cause unintentional transformations and the Omnitrix will be unable to deactivate until the source of the interference is gone. This is how Tiffin was unintentionally sending signals that caused the Omnitrix to malfunction, turning Ben into Rath. It also can work in reverse, rapidly changing the user from one form to another until someone/something stops it.
- The Omnitrix is able to repair genetic damage. It is unknown if this can change hybrids such as Manny and Helen to their full Human/Tetramand/Kineceleran forms.
- The Omnitrix can genetically manipulate DNA or reprogram a species' DNA (like fuse DNA from different species of aliens).
- The Omnitrix in Alien Force is green because it is working correctly, which also meant it wasn't working as it should during the original series. The Omnitrix is in the center around the chest area on every alien in Alien Force is for easy access. The symbol was put in different places on some aliens (head on Ditto, back on Grey Matter, etc.) in the original series which was a side effect of the Omnitrix not working properly (which explains why all the symbols were moved to the chest in Alien Force since it is now working right).
- If the Omnitrix's faceplate cover is broken off, the result is DNA hybrids.
- Azmuth has is creating a new Omnitrix but, due to the fact that it is not ready and Ben is not ready it for because of his immaturity, he hasn't given it to Ben yet.