Google reCAPTCHA blocks bots and spammers from polluting your subscription forms in just a few clicks. Here's how to add it to your Mailpro signup form or any web form in under 5 minutes.
Pro tip: reCAPTCHA v3 is invisible to legitimate users. They don't see a checkbox or puzzle — Google scores the visit and blocks bots silently.
Step 1 — Get your reCAPTCHA keys
- Go to the Google reCAPTCHA admin console.
- Click + to register a new site.
- Pick reCAPTCHA v2 "I'm not a robot" or v3 (invisible).
- Add your domain (e.g.
example.com). - Accept the terms and click Submit.
- Copy the Site Key and Secret Key.
Step 2 — Paste them into your Mailpro form
- Sign in to Mailpro and open the Forms module.
- Edit your subscription form.
- In Security → Captcha, paste the Site Key and Secret Key.
- Save and re-publish the form.
Step 3 — Verify it works
- Open your form on the live page in an incognito window.
- Submit a test entry — the captcha should run successfully.
- Check the statistics dashboard for blocked attempts.
Best practices
- Combine reCAPTCHA with double opt-in for extra safety.
- Add an honeypot field for older bots that don't even reach reCAPTCHA.
- Rotate the secret key once a year, or after any leak.
- Always show a privacy note linking to Google's privacy policy (GDPR).
Bot-proof signup forms — free with Mailpro
Mailpro forms include reCAPTCHA, double opt-in, customizable design and direct sync to your contact list. Discover Mailpro Forms · Sign-up form feature
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