In order to prevent spam being submitted on the Guestbook comments form, we have added a new section. To successfully submit a comment, a simple numerical question must be answered by selecting the correct answer from a dropdown list. The questions ask for answers to the sum of random numbers. This is our first attempt at solving the spam issue. If the problem continues, we will refine our spam prevention techniques.
Guestbook spam isn’t just annoying—it can:
That’s why ReservationKey introduced a simple dropdown math question—a smart first step in spam prevention
As ReservationKey does, present a random arithmetic question and require selecting the correct result. This catches basic bots easily
Use image or checkbox-based CAPTCHAs. Nearly every platform (Jimdo, InMotion, etc.) recommends them as a baseline anti-spam measure
Add a hidden form field that only bots will fill. Since real users don’t see it, submissions that include it are automatically flagged as spam help.jimdo.com.
Render the form dynamically using JavaScript or Flash so bots that scroll raw HTML won’t see it aoeex.com. Just be cautious—some users disable scripts.
Set entries to moderation, or require email confirmation before entries get posted. This ensures you approve legitimate posts only inmotionhosting.com.
Blacklist repeat offenders at the IP or email level. While not foolproof—spammers use dynamic IPs—it helps reduce persistent abuse nutshell.com.
Use services like CleanTalk, ProCaptcha Guestbook, or WordPress plugins. These integrate seamlessly and significantly reduce spam with minimal setup snaphost.com.
Combining methods creates a strong defense:
TechniqueStrengthsMath dropdown + CAPTCHABlocks bots & basic scriptsHoneypot + JS-form renderingSneaks up on sophisticated botsModeration & blockingAdmin control and targeted defensesThird-party pluginsAccuracy with analytics and logs
ReservationKey’s 2012 solution:
Founded in 2007, ReservationKey was created to offer a simple, yet powerful and affordable solution for managing reservations and displaying availability online. Our goal is to deliver top-quality software that fulfills our users' needs - simple, efficient, and budget-friendly.
