Google’s Tone Chrome Extension Lets You Share URLs By Sound

Google launched an experimental Chrome extension today that lets you share the URL from your current browser tab with anybody within earshot. Tone, which is now available in the Chrome Web Store, uses sound to transmit the information and uses the speakers and microphones now typically available on any laptop.

Because it’s audio-based, it has some interesting limitations: the information doesn’t carry very far, for example, and any wall will block it.

As the Google Research team behind the extension notes in today’s announcement, the first version was very efficient, but it sounded horrible. The team then moved to a codec that would play the sound beyond the limits of human hearing, but laptop microphones tend to be optimized for voice, so that didn’t really work all that well.

The version that launched today now uses a “dual-tone multi-frequency signaling” system, similar to what telephone systems use. That means you will hear a short sequence of beeps when you hit the ‘Tone’ button in Chrome after installing the extension. The machines that pick up the sound will pop up a notification and clicking on that will open the shared URL.

Ideally. every machine that also has the extension installed will pick up the transmission, but as the developers note, this may not always work.

“Not every nearby machine will always receive every broadcast, just like not everyone will always hear every word someone says,” Google’s Alex Kauffmann and Boris Smus explain in today’s announcement. “But resending is painless and debugging generally just requires raising the volume.”

Google already uses a similar technology to allow phones to talk to its Chromecast devices over audio, but that’s happening outside of the reach of human hearing and uses a different technology.

I’m not sure how useful this really is, but it’s a cool experiment. You can now download the extension here. Let us know how it worked for you in the comments.