One day you woke up and feel excited that you got thousands responses for your Google forms survey. When you opened the spreadsheet, you’re staggered. Most of responses are garbage spams.

You may be surprised that these malicious bot spam tools does exist in the market, such as this Google Form Submitter. (Thanks to Google, it ranks the first so it’s easy for anyone to find and hack. 😂)

Some guys hope reCAPTCHA to be integrated with Google Forms. At least at the moment of writing this article, such integration is yet to come.

So how do you fight your forms from being spammed? We shows you 3 imperfect workarounds to reduce spams. Just like flu, we can get flu shots for a season protection, but we cannot be immune from spams forever.

Method 1. Password protection

First of all, we assume you published a naked google form on social medias or embedded in your own site. Anyone can discover the form link and submit answers without any restrictions.

The old school password strategy is easy to understand.

Pros

  • Secure. If you have a long strong password, it’s hard for spammers to break into.
  • Simple to implement.

Cons

  • Dilemma. If you don’t share the password with the public link, no one can submit any answer. If you shared, it makes no senses.

Here is how it works.

  • Open your Google form.
  • Add a Short answer question, named Password.
  • Click the icon
  • Click Response validation.
Add a password short text question with response validation
Add a Password short answer question with response validation
  • In the validation conditions, select Regular expression Matches
  • Type in a long and strong password and an error message when respondents typed a wrong password.
  • Turn on Required.
Text validation for password short answer. select text contains some long password. and write some text message if password is incorrect.
Text Validation for password short answer
  • Now try to submit a response with a wrong password. You will find you cannot. It tells you the password is incorrect.
Wrong password will stop you from submitting spam answers. It prompts your password is incorrect
Wrong password will stop you from submitting spam answers

Method 2. Limit only 1 response

This method is apparently the easiest since it’s one click. This method will more or less slow down spammers and thus decrease the number of spams.

Pros

  • Secure.
  • Easiest to do.

Cons

  • Limited to google users.
  • May lower conversion rate for the extra step.

Here is how it works.

  • Open your Google form.
  • Click Settings.
  • In the General tab, check the Limit to 1 response option.
Limit to 1 response option in Google forms settings
Limit to 1 response option in Google forms settings
  • When you are done, any respondents without their google accounts logged in will see the following screen.
when a respondent opens a form, a Google Account sign in dialog pops up to demand signing in before filling the form
Google account sign-in required to fill the form
  • When they want to re-submit another spam answer, they will be blocked.
You've already responded message shown after you try to submit another response. It tells you you can only fill out this form once. Try contacting the owner of the form.
You’ve already responded message shown after you try to submit another response

Method 3. Simulated CAPTCHA

This method relies on a form addon to work, named Captcha for Forms. It adds an additional security layer without compromise of flexibility. The addon adds a dynamic captcha code challenge for respondents. Unlike the dilemma using password method above, the tool is able to expire the captcha frequently so no permanent spamming is possible.

Let’s take a look how it works.

  • Once you are done with installation, open Captcha for Forms from the menu.
  • In the popped sidebar, turn on Enable Captcha.
  • That’s it, simple.
Captcha for forms adds a code challenge to respondents to protect forms from spams
Captcha for forms adds a code challenge to respondents to protect forms from spams

Now let’s see the respondent’s screen.

Bots cannot easily get through a dynamic challenge
Bots cannot easily get through a dynamic challenge
  • It’s difficult for bot to respond the captcha challenge but human.

Conclusion

Anti-spam is an endless game. Please leave any comments if you have any questions.