How do you stop spam entries on webforms?

We’ve been using a service called ListCleaner which looks at records as they are created in your Keap account and then takes action based on whether they look legitimate or not (obvious spam is deleted, fishy-looking records are tagged, good contacts are also tagged as such).

This service has since become unreliable and we’re struggling to get it working correctly so we’re looking for an alternative. The existing spam protection on the forms aren’t effective enough, spam is coming through despite the captcha, likely to be manual entries to some extent.

We’re looking for a similar service that looks at the actual data entered into the fields to determine whether the contact is legitimate or not, does anybody have any suggestions?

Thanks,
Joe

SpamKill is one suggestion - https://spamkill.co/

There has been discussions about this in the past, like here: Best way to combat spam form submissions? - #11 by Matt_Ludwig

Captcha sounded like a good idea in the past, but the spammers try different tactics to get around things.