How to check data usage on android phone?

Checking Overall Data Consumed
1. Open the Settings menu. From your #Android
home screen, app drawer, or notification panel, tap the gear shaped icon. This will open your device’s Settings menu.
2. Select “Data Usage” near the top of the
Settings menu.
This will open the Data Usage screen. The screen will display the overall
amount of data used at the top of the screen.
3. Check the overall data consumed. The overall data consumed is shown at the top of the
screen. You can check the overall data amount
you've used for a certain period by tapping the “Data usage cycle” box at the top right corner of
the screen. Enter the period from which you
would like to check your data usage then tap
“OK.” The changes will be displayed at the top
of the screen.Your Android device will not
automatically line the dates up with your
monthly billing cycle, so you’ll need to set your
billing date manually.
4. Check data usage of applications. Below the
overall data amount used, a list of applications
is displayed. The list shows the amount of data
used individually by each app.

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