Generate Google reCAPTCHA Keys

What reCAPTCHA is

reCAPTCHA is a free service by Google that tells humans from bots. It protects login, contact and sign-up forms from spam. There are three main types:

1. v2 Checkbox. The familiar "I'm not a robot" box.
2. v2 Invisible. It works in the background and asks only when it is unsure.
3. v3 Score-based. It gives each visit a score and needs no user action.

Create the keys

1. Open the Google reCAPTCHA Admin Console on the official Google website.
2. Sign in with your Google account (a free account is enough).
3. Click the + button at the top right.
4. Fill in the registration form:

   

   
   - Label. A name that helps you remember the site.
   - reCAPTCHA type. The version you want to use.
   - Domains. The domain names where you will use the keys.
   - Owners. Your email address is filled in. You can add more owners.
5. Read and accept the reCAPTCHA terms of service, and click Submit.
6. Google shows a Site Key and a Secret Key.

   

Use the keys

1. Add the reCAPTCHA JavaScript library to your pages (Google gives you the code).
2. Use the Site Key to show the reCAPTCHA in your form.
3. Send the response token with the form to your server.
4. On your server, send a verification request to Google with the Secret Key and the token.
5. Google answers with JSON that says if the check passed. For v3 it also gives a score.

In WordPress, plugins such as Contact Form 7 or a dedicated reCAPTCHA plugin only need the two keys. Paste them in the plugin settings.

Notes

• reCAPTCHA Enterprise is a paid service with more features.
• Add localhost to the domain list if you test on your own computer.
• Test the form after you add reCAPTCHA.

Quick recap

• Register your site in the reCAPTCHA Admin Console.
• Use the Site Key in the page and the Secret Key on the server.
• Keep the Secret Key private.