In the office or at home, you can block access to the Facebook website on Google Chrome. You can use Block Site or Nanny extensions which are free for this browser. You cannot block Facebook in the Google Chrome mobile app.
Steps
Method 1 of 2: Use Block Site

Step 1. Go to the Block Site extension page
The Block Site window will open.

Step 2. Click + ADD TO CHROME
It's the blue button at the top right of the Block Site window.

Step 3. Select Add Extension
This will install the Block Site extension.

Step 4. Refresh Chrome
Click on ⟳ at the top left of the window. This will refresh Chrome and place the Block Site icon at the top right of the Chrome browser.

Step 5. Click on the Block Site icon
It looks like a "www" with a circle and a slash across. You'll find it at the top right of the Chrome window. A drop-down menu will open.

Step 6. Select Options
This option is in the drop-down menu. A new tab with Block Site settings will open.

Step 7. Enter the Facebook address
Type in the field Add a page at the top of the page.

Step 8. Click Add Page
It's the green button to the right of the field Add a page. Facebook will be added to Block Site's block list. When a user tries to open Facebook, Block Site will immediately redirect them to a different page.
- You can enter a second address (for example, https://www.google.com/) in the text field Redirect to next to the Facebook address to open it when people try to open Facebook.

Step 9. Select Close
It's the blue button at the bottom of the page. It closes Block Site. Facebook will remain blocked until you unblock it.
Method 2 of 2: Use Nanny

Step 1. Open the Nanny extension page
Nanny's window will open.

Step 2. Click + ADD TO CHROME
It's the blue button at the top right of the window.

Step 3. Select Add Extension
This will install the Nanny extension.

Step 4. Right click on the Nanny icon
It looks like a watch at the top right of the browser window. Right click on it to open a drop down menu.
- If your mouse does not have a right button, use 2 fingers to press the trackpad on your computer.
- On a Mac, you can press Control and click the icon.

Step 5. Click Options
This option is at the top of the drop-down menu and opens the Nanny page.

Step 6. Open the Blocked URLs tab
You will find it at the top left of the page.

Step 7. Enter a name for your blocked addresses list
Type a name in the field Block Set Name at the top of the page.
Since you are only blocking Facebook, you can name this list “Social networks” or “Facebook only”

Step 8. Enter the Facebook address
Type in the field Urls.

Step 9. Select a blocking period
Type the start time and the end time of the blocking (in military time) in the field Block Time.
For example, to block the site from 11:00 a.m. to 5:00 p.m. and from 9:00 p.m. to 8:00 a.m., you would type 1100-1700, 2100-0800

Step 10. Make sure all days are checked
In the row Apply On Days, make sure there is a check mark next to the days of the week you want to block Facebook for.

Step 11. Click Set URL
This button is located at the bottom right of the page. Your settings will be saved and Facebook will be blocked during the selected time period.