How to set Captcha in Magento 2

Having a Captcha on your store is quite important. Captcha or Completely Automated Public Turing test to Tell Computers and Humans Apart is a technique to distinguish between humans and computers. Captcha is mainly used as a security check to ensure only human users can pass through. 

To set it up, follow the below steps:

1. Set CAPTCHA for Admin Store For extra security measurements you can add CAPTCHA to the Admin Sign in page.

To set it up, go to Admin -> Stores -> Settings -> Configuration -> Advanced -> Admin -> Scope: Select Store -> Captcha:

• Enable CAPTCHA in Admin [Yes / No] Set to Yes if you want Captcha to appear on Admin Page.
• Font The font is set to default: LinLibertine.
• Forms If you want to set both options, press CTRL and select also the second option.
• Displaying Mode [Always / After a number of attempts to login]
• Number of Unsuccessful Attempts to Login If 0 is specified, CAPTCHA on the Login form will be always available.
• CAPTCHA Timeout (minutes) Set the number of minutes before the CAPTCHA expires. After the CAPTCHA expires the Admin needs to reload the page before attempting again.
• Number of Symbols Set up to 8 symbols. The range allowed (e.g. 3-5).
• Symbols Used in CAPTCHA Enter a-z(A-Z) letters and numbers from 0-9 that you want to randomly appear in the CAPTCHA.
• Case Sensitive [Yes / No] Set to Yes if you want the Admin/s to enter the exact upper and lowercase like in the CAPTCHA image.

Click Save Config.

2. Set CAPTCHA for the Storefront You can set CAPTCHA for the customer to appear each time they log in or after a few unsuccessful attempts to log in.

To set it up, go to Admin -> Stores -> Settings -> Configuration -> Customers -> Customer Configuration -> CAPTCHA:

• Enable CAPTCHA on Storefront [Yes / No] Enable or Disable CAPTCHA for the customers
• Font The font is set to default: LinLibertine.
• Forms If you want to set both options, press CTRL and select where the CAPTCHA to appear, you have the options presented in the image above.
• Displaying Mode [Always / After a number of attempts to login]
• Number of Unsuccessful Attempts to Login If 0 is specified, CAPTCHA on the Login form will be always available.
• CAPTCHA Timeout (minutes) Set the number of minutes before the CAPTCHA expires. After the CAPTCHA expires the Admin needs to reload the page before attempting again.
• Number of Symbols Set up to 8 symbols. The range allowed (e.g. 3-5).
• Symbols Used in CAPTCHA Enter a-z(A-Z) letters and numbers from 0-9 that you want to randomly appear in the CAPTCHA.
• Case Sensitive [Yes / No] Set to Yes if you want the Admin/s to enter the exact upper and lowercase like in the CAPTCHA image.

Click Save Config.

If you want to set also reCAPTCHA for the store, follow these steps here: