The instructions apply to all Logitech wireless keyboard models.
How Do You Charge a Logitech Wireless Keyboard?
Use the charging cable included with your keyboard.

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If you don’t have the original charger, you’re free to use any micro-USB connector.
Look for a removable plate on the bottom of the keyboard to find and replace the batteries.
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Where Is the Charging Port on a Logitech Keyboard?
The micro-USB charging port is on the back of the rig, usually on the right side.
The exact location may differ depending on the model.
If you don’t have the manual, try searching for your exact model number.
How Do I Know My Logitech Keyboard Is Charged?
The status light on your keyboard will flash while the battery is charging.
The light will turn solid when it’s fully charged.
When your keyboard is low on power, the status light will flash briefly when you turn it on.
After you drop in the program, it will detect your keyboard.
In the interface, you’ve got the option to see the battery status.
Turn off the keyboard when you’re not using it to extend battery life.
Why Won’t My Logitech Keyboard Charge?
The charging cable could be damaged, so try using a different one.
There could also be a problem with the charging port.
When the status light is green, the keyboard is sufficiently charged.
It can take an hour or more to fully charge the battery on your Logitech keyboard.
If your keyboard supports multiple connections, press a connection button or set the dial to the desired connection.