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8 Ways to Combat Form Spam

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If you use forms on your website, you’ve likely encountered at least a few instances of form spam. The impacts of form spam can range from wasted time to decreased user trust. While you can’t ensure that users always use your forms how you intended, you can take steps to significantly reduce the amount of spam your forms get. 

Want to learn more about form spam and how to prevent it? Just keep reading!

What is form spam?

Form spam is the submission of online forms with malicious intent. Both bots and human spammers can submit form spam and may include false, irrelevant, or inappropriate information or spam links or scripts in their submissions. Any type of form can receive spam, including forms that allow users to comment on web pages, contact forms, and payment forms.  

Why does form spam happen?

Spam form submissions occur for various reasons. A few common examples include:

  • Spammers may submit links to their website in your forms in hopes of the link ending up on your website in a comment or elsewhere in order to boost their search engine optimization (SEO)
  • Spammers may submit malicious links that are designed to inject viruses, steal sensitive information, or restrict access to your site.
  • Spammers may send empty offers to a large swath of websites, such as promising to rank your website as the first result in Google searches, when in reality they have no intention of actually doing so.

Why is it important to prevent form spam?

The impacts of form spam range from annoyance to potential security risks. Here are a few reasons it’s important to stop spammers and bots from submitting forms:

  • Form spam wastes your time: Having to go through fake leads or contact form submissions takes your time away from leads and customers that need your attention, potentially leading to missed opportunities and decreased customer satisfaction.
  • Form spam can skew your data: For example, if you receive a large influx of fake leads through a form, you will need to spend time cleaning up your data to keep it accurate.
  • Malicious links sent through form spam can pose security risks: They may cause financial harm, cause downtime, and decrease trust in your brand. It’s important to never click suspicious links submitted through your forms.

Fortifying your defenses: Top techniques for contact form spam protection

So, how can you go about preventing form spam? Here are some of the best techniques to use.


CAPTCHA is one of the most common ways to prevent automated form spam. These anti-spam measures present tests that are designed to be solvable by humans but not by bots, such as identifying a word in a stretched or distorted image or selecting images that match a prompt.

When using CAPTCHAs, it’s important to balance sophistication to stop bots from submitting forms and ensure ease of use for legitimate human users.

2. The honeypot method

The honeypot method aims to “trap” bots with hidden form fields. Since humans won’t see these fields, whenever they’re filled, you know you’re receiving an automated submission. This is just one of the many ways to prevent form spam without CAPTCHA.

3. Blocking forms once a user completes them

If you’re finding that spam bots or human spammers are submitting the same form multiple times, a simple way to reduce spam submissions is to only allow users to fill out the form once. To implement this measure, set a form to be disabled or inaccessible after it’s been successfully submitted once per user or per session.

Of course, this may not be the ideal method if legitimate users might submit a form multiple times during a session, such as with a contact form.

4. Blocking specific email or IP addresses

Collecting email or IP addresses can help you prevent form spam. If you notice spam coming in from specific email or IP addresses, you can block those addresses from accessing your forms or flag submissions from them as spam.

5. Asking questions in your form

Another technique you can use to prevent form spam without CAPTCHA is to create a form field that asks visitors a question they have to answer correctly before submitting their form.

You might include a basic text or math question, such as:

  • What comes first in the alphabet, C or Y?
  • What is 5+3?
  • What is the first letter in the word “dog?”

6. User authentication and validation

Another method for preventing spam bots and humans from adding spam form submissions is user authentication. This includes techniques like requiring users to verify their email addresses or complete two-factor authentication before submitting a form.

This method is best used on higher-value forms such as trial signups rather than things like contact forms or PDF download forms. Users may not feel that it’s worth going through the extra steps required for authentication for lower-value forms, so it’s important to consider the potential impact on conversions before implementing these techniques.

7. Plugins and anti-spam services

Third-party services and plugins are a great way to get more comprehensive contact form spam protection. If you use a platform like WordPress, there are various spam prevention plugin options available. You can also opt for cloud-based anti-spam services that filter out spammy form submissions in real time.

8. Analyzing and monitoring form activity

It’s also helpful to keep an eye on your form submissions, as well as analytics for your forms. Regularly monitoring your form submissions can help you identify unusual patterns and activity.

Leverage the power of online forms—without the spam

If you use forms on your website, you need to be prepared to prevent and address form spam. Using the techniques we discussed in this blog post can help you avoid wasted time, inaccurate data, and security risks.

And if you’re looking for an easy way to add forms to your website, consider Nutshell. With Nutshell, you get a flexible, user-friendly form builder right in your CRM. When you use Nutshell Forms, new contacts are automatically added to your CRM, making it easier than ever to quickly reach out to them.

To try Nutshell Forms for yourself, start a 14-day free trial of Nutshell today.

Need to design eye-catching forms for your website?

Use Nutshell Forms, an easy-to-use form builder that fits right into your CRM.

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