T-Mobile is opening registration today for a beta test of Live Translation, an AI-powered feature that will translate live phone calls into more than 50 languages when it launches this spring.

The feature operates at the network level, so it doesn't require any specific app or device -- beta participants simply dial 87 to activate it on a call. T-Mobile President of Technology and CTO John Saw told The Verge that Live Translation works over VoLTE, VoNR and VoWiFi, meaning it isn't limited to 5G. The only requirement is that a T-Mobile customer must initiate the translation. The beta will be free, though T-Mobile has not said whether the feature will eventually be paywalled.