Your Google Duo calls & meetings stay private with encryption

Google Duo has been upgraded to include both video calling and meeting capabilities. When communicating in Duo, you can use either:

• 1:1 and group video calling: The classic Duo end-to-end encrypted experience that involves ringing a number or group directly.
• Meetings: The ability to create or join a cloud-encrypted Google Meet meeting with a link when you’re ready. Meet meetings happen in the Duo app. 

Available features  and encryption methods are different between video calling and meetings.

Learn more about the upgrade.

To keep your conversations private, Duo uses end-to-end encryption for 1:1 and group video calling and cloud encryption for meetings joined or created in Duo.

• Only people in a call or meeting know what’s said or shown.
• Google can’t view, hear, or save audio or video from your call or meeting.

To make sure your data is safe, Google Duo uses multiple encryption methods. 

• For 1:1 and group video calling: End-to-end encryption is used to mask data with a code that only you and the other callers can access.
• For Meet meetings in the Duo app: Cloud encryption is used to encrypt your meeting data in transit and stored information in Google's data centers instead of end-to-end encryption.

Tip:  To add an additional layer of protection, organizations can also use client-side encryption to have full control of their encryption keys. Learn more about client-side encryption.

End-to-end encryption is a standard security method that protects communications data. It's built into every Duo 1:1 and group video call, so you don’t need to turn it on yourself, and it can’t be turned off.

How end-to-end encryption & cloud encryption differ

End-to-end encryption for 1:1 and group video calling:

• Is a standard security method that protects communications data 
• Is on by default and can’t be turned off 
• Only lets people in a call know what’s said or shown
• Doesn’t allow Google to view, hear, or save the audio and video from your call
• Masks the call data with a code that requires a key to decode

Cloud encryption for meetings:

• By default, meeting data in the Duo app is encrypted in transit between the client and Google data centers for any video meetings taking place in Google Duo or Google Meet. 
• By default, meeting recordings enabled by a meeting participant are stored in Google Drive and encrypted.
• Meeting encryption adheres to:
  • Internet Engineering Task Force security standards for Datagram Transport Layer Security (DTLS)
  • Secure Real-time Transport Protocol (SRTP)

Learn about call and meeting encryption in Google Duo.

How we protect your data in one-to-one calls

Shared secret keys stay on the callers’ devices

Your device decrypts your call’s audio and video with a shared secret key. This key is created on your device and your contact’s device and is deleted after the call ends. It’s not shared with any server.

What’s needed for a shared key

To calculate the shared key, each device needs:

• A private key, which is saved only on your device
• A public key, which is saved on Duo’s servers

The first time you set up Duo, your device creates several private/public key pairs. This way, you’re ready for several end-to-end encrypted calls.

How shared secret keys are created

• The devices exchange their public keys but don’t reveal their private keys.
• Next, each device uses its private key and the public key from the other device to calculate the shared secret key. They use a mathematical process called cryptography.

Google servers can’t decode your call

When you call someone else on Duo, your call’s audio and video typically go directly from your device to their device. This connection is called peer-to-peer. The call doesn’t go through a Google server.

However, sometimes a peer-to-peer connection isn't available, like if a network setting blocks it. In this case, a Google relay server passes a call’s audio and video between your device and the device you called. The server can’t decode your call because it doesn’t have the shared secret key.

How we protect your data in group calls

Group calls stay private on the server

Group calls are also end-to-end encrypted. To make sure group calls are high-quality, they go through a Google server.

That server routes everyone’s call audio and video to others in the group. To route calls, the server uses info about your call, like which device the video is from. The server doesn't have access to the end-to-end keys and can't decrypt the media.

Group calls use multiple keys

To be part of a call that goes through a server, each group member’s device automatically uses:

• A sender key to encrypt the call’s audio and video. When someone starts a group call, each device exchanges this key with the other devices.
• A client-to-server key to encrypt info about the call. Each device exchanges this key with the server.

What the keys do

The keys work to:

• Encrypt your call’s audio and video so that only other people in the group can hear and see it.
• Decode the audio, video, and info from other people in the group call.

Keys can change during group calls

Everyone’s devices exchange new sender keys if either:

• Someone leaves a group
• A person who wasn’t part of the group gets added to it during the call

If a person in the group doesn’t immediately join the group call, their device can still use everyone’s sender keys. This way, that person can join the call anytime while it’s live.

When the group call ends, the keys are deleted.