Stop fake sign-ups on your Mailchimp for WordPress forms
Procaptcha is already built into Mailchimp for WordPress (MC4WP). There is nothing else to install. You only need a free site key and secret key from Prosopo, and your forms stop sending bot sign-ups to your Mailchimp list.
Free for 10,000 verifications a month. No credit card, no cookies, no cookie-banner entry.
Set it up in three steps
- 1
Get your keys
Sign up for a free Prosopo account with your name, email and your website's address. In the Prosopo portal, open Site management and copy your Site Key and Secret Key.
- 2
Paste them into MC4WP
In WordPress, go to MC4WP → Integrations → Procaptcha (by Prosopo). Paste the Site Key and Secret Key and save. Procaptcha switches on as soon as both keys are saved, and a preview captcha appears on the settings page. If you can complete the preview, your keys work.
- 3
Add the field to your form
Go to MC4WP → Form, click the Procaptcha field in the list of available fields, add it to the form above the submit button, and save. Every sign-up through that form is now checked.
Why can't I see the captcha on my MC4WP form?
By default MC4WP does not show the captcha to visitors who are logged in to WordPress, so you won't see it while you are logged in as admin. Open the page in a private window to check, or set Display for authorized users to Yes in the Procaptcha integration settings.
Which captcha type should I choose?
The Procaptcha integration settings offer three types:
- Frictionless. The default, and the one we recommend. Most visitors see nothing to solve. Procaptcha only shows a challenge when a visitor looks like a bot.
- Proof of Work. The visitor's browser does a short calculation. Nothing to click or solve.
- Image Captcha. Every visitor picks matching images before they can sign up.
Why do bots sign up to Mailchimp lists?
Bots fill in newsletter forms to test stolen email addresses, to send welcome emails to people who never asked for them, or just because the form is there. Every fake sign-up counts towards your Mailchimp contact limit, the confirmation emails bounce or get marked as spam, and a high bounce rate hurts the delivery of the emails your real subscribers want. A captcha stops the bot before it reaches Mailchimp.
Is Procaptcha free for MC4WP?
Yes. The free plan covers 10,000 verifications a month, which is more than most newsletter forms ever see. You don't need a credit card to sign up. If you need more, see pricing.
Is Procaptcha GDPR-compliant?
Yes. Procaptcha sets no cookies and doesn't track your visitors across sites, so it doesn't need an entry in your cookie banner.
Can I use the same keys with other WordPress form plugins?
Yes. For forms that aren't made with MC4WP, such as Contact Form 7, WPForms or Gravity Forms, use the Prosopo Procaptcha WordPress plugin with the same site key and secret key.
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