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Do you have a subscribe form on your site, but are worried about the rising tide of signup form spam? Or, perhaps you want to use your subscribe form in a competition and don’t want to attract thousands of automated entries? Lets step through two ways you can expand on your subscribe forms to protect them from unwanted signups, while not having to tear your site code to pieces in the process.

#1: Use reCAPTCHA with your subscribe form

I’m sure you’ve all seen (and used) a form with a CAPTCHA. In essence, it’s a test to make sure that you’re human, by making you interpret and type out scrambled letters, solve a problem, or essentially do something that a computer can’t do:


The most flexible way to add a CAPTCHA to a subscribe form is to use an existing service like Google’s reCAPTCHA (above). reCAPTCHA provides the necessary form code and plugins required, alongside loads of documentation on installing and customizing a CAPTCHA form on your site. Even better, CAPTCHA answers are used to assist in digitizing old books!

You can also tweak how the CAPTCHA looks in your form. Alongside a set of standard themes are instructions to help you customize it as you see fit.

Of course, there are major reasons why you shouldn’t be forcing CAPTCHA on all your new signups. They can drop conversion rates as they lengthen forms and can be hard to interpret, they’re not fail-safe against human spammers and are potentially unusable by people who are blind, partially-sighted or suffer from dyslexia. Which leads us to the other option…

#2: Use a Wufoo subscribe form

Now that Wufoo can populate your custom fields, there’s no reason why you can’t create a subscribe form and synchronize it with your Campaign Monitor list. This also allows you to use some of Wufoo’s excellent form features, such as conditional logic, or only adding subscribers that tick an ‘I agree to receive email…’ box:


The icing on the cake is that Wufoo can automatically display a CAPTCHA if it thinks that someone’s abusing your subscribe form. This is great, as it means the CAPTCHA isn’t visible by default, thus it has no impact on subscribe rates. You can also limit form use to one entry per IP, although use this with care (it could impact folks trying to subscribe via public machines).

Wufoo forms can be both standalone, or embedded in your site. You can set up a free account for up to 3 forms/10 fields/100 entries a month.

Keeping in mind that there’s no silver bullet when it comes to keeping the spammers at bay, it’s really up to your discretion as to whether you want to verify all signups, or not. Although these methods can ensure that most of your subscribers are real, living human beings, how you implement it can affect signup rates and even exclude members of the community from using your subscribe forms (CAPTCHA), or simply require a little extra legwork… And potentially, money (Wufoo). But sometimes, that’s the price to pay for a little peace of mind.

This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.
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