Android System Key Verifier

The Android System Key Verifier is a system service designed to improve the security of end-to-end encrypted (E2EE) messaging apps. It provides a unified system for public key verification across different apps. This lets you verify the public keys of your contacts and confirm that you're communicating with the person you intend to message over Rich Communication Services (RCS).

What you need

Important: The key verification feature isn’t supported on Android Go devices, tablets, and wearables.

Verify a contact’s key

You can use the Android System Key Verifier in the Google Contacts and Google Messages apps.

Verify a contact’s keys from Google Contacts

  1. On your device, open the Google Contacts app .

  2. Tap the contact you want to verify.

  3. Under "Contact settings," tap Verify keys.

  4. To complete the key verification, follow the on-screen instructions.

    • Be sure that both you and your contact scan QR codes on each other’s devices and complete all steps. You can scan a screenshot of your contact’s QR code.

Verify a contact’s keys from Google Messages

  1. Open the Google Messages app .

  2. Select a chat with the contact you want to verify.

    • You can open a chat with a contact without messaging them.

  3. From the top of the screen, tap the contact’s name or More More and then Details and then Verify keys.

  4. To complete key verification, follow the on-screen instructions.

Verify a contact's keys from a group conversation in Google Messages

  1. Open the Google Messages app .

  2. Open the group conversation with the contact you want to verify.

  3. Tap the group’s name or More More and then Group Details.

  4. In the group details page, scroll to the contact you want to verify.

  5. To verify the contact’s keys, next to the contact’s name, tap More More and then Verify keys.

    • Or, you can:

      1. Touch and hold the contact's name.

      2. Tap Information .

      3. Verify a contact on Google Contacts .

      4. Follow the on-screen instructions.

Check the verification status of contact keys

  • When the contact keys are verified, you can check the verification status in:

    • Google Contacts:

      1. Open the Google Contacts app .

      2. Open the contact you’d like to check the status for.

      3. Under "Connected apps," check if a list of apps appear.

        • The "Connected apps" section appears for a specific contact only when its contact key is verified.

    • Google Messages:

      • Contact details: Check the contact’s details in Google Messages app .

      • Group details: Check the group’s details in the Google Messages under the specific contact.

  • Verified contacts have keys verified status or Keys verified . Those with lapsed verification have keys no longer verified status or Keys no longer verified .

Why a contact’s keys could change

If a contact’s keys change, their status displays as Keys no longer verified .

Your contact’s keys could change if:

  • Your contact gets a new device or SIM card.

  • The contact keys’ time-bound validity expires.

  • There’s an upgrade to the underlying encryption protocol.

A contact’s keys could also change due to malicious attacks:

  • Man-in-the-middle attack: If a malicious party intercepts the initial key exchange and replaces the keys with their own.

  • SIM swapping: If a malicious party convinces a carrier to transfer a phone number that they don't own to a SIM card they control.

Troubleshoot Key Verifier

I got a "Setting up key verification" screen

If you received this message, the service is being set up.

To dismiss the message, you can either:

  • Tap the close button.

  • Swipe down.

  • Tap anywhere outside of the message.

Contact’s keys not available for verification

If there are no keys available for verification, your phone or your contact’s phone may not meet the requirements. Learn about what you need to use the Key Verifier.

There are few cases, depends on the scenario:

  • If your contact is on a different OS, key verification isn’t available at this time.

  • If there are no stored keys, you need to open a conversation in Google Messages with your contact.

    • There’s no need to send the message.

  • If your contact uninstalled the Android System Key Verifier, you need to have your contact reinstall it to complete the verification process.

  • If your contact’s phone number is a landline, the key verification isn’t available.

  • If you or your contact is on Android, but either doesn't support RCS completely or supports RCS but not end-to-end encryption RCS, the key verification isn’t available.

QR code scanned but get Question mark

If you find a question mark after you scan a contact’s QR code, the code doesn’t match with the device and contact. Make sure you scan the correct QR code or device for the contact.

QR code scanned but get Yellow Shield crossed out

If you find a yellow shield with a cross after you scan a contact's QR code, an issue occurs when they verify their encryption keys. Make sure your RCS end-to-end encryption is on for the contact, try to initiate a conversation with the contact or send a message and verify the contact again.

QR code not available

If you get an empty box instead of your QR code, it means your QR isn't available and a technical problem prevents code generation. Restart the app, then open the QR code again.

How Google uses your data

In order to monitor and improve its performance, Android System Key Verifier optionally collects:

  • Crash logs
  • Diagnostics and performance data like API latency
  • Device or account identifiers

Important: This data is collected only to help monitor the performance and the quality of the Android System Key Verifier app. Your private keys are never sent to Google.

You’re in control of your data

The analytics data collection is entirely optional and can be controlled through the "Usage & diagnostics" setting. Learn about sharing usage & diagnostics information with Google.

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