Akismet is a content filter — it reads what bots write and guesses whether it's spam. SpamKill analyzes how bots behave and stops them before they ever submit. Different approach, dramatically different results.
If you are here because Akismet wants a paid plan for your business site, start with the free SpamKill plugin. It protects WordPress comments and WooCommerce product reviews with no signup, no API key and no CAPTCHA, and the free tier covers commercial sites.
Akismet's WordPress.org listing states that keys are free for personal blogs and that paid subscriptions are available for businesses and commercial sites. In a support-forum reply in July 2026, Akismet staff wrote that any business usage must use a paid plan. Akismet Pro is one site and 500 spam checks a month, billed yearly.
Comment and review protection is free on any site, commercial or not, with no key and no monthly allowance. Contact-form protection is the paid tier, from $29 a month, with a 30-day trial.
Akismet asks: "Does this text look like spam?" SpamKill asks: "Does this visitor behave like a bot?"
Akismet analyzes submission content — the text, links, email addresses — and compares it against a global spam database. It flags what looks like spam after the submission is already made.
• AI-written spam with clean text passes right through
• Spam still enters your database — just gets flagged
• False positives on legitimate content with spam-like words
• WordPress-only (comments + supported form plugins)
• No protection for lead gen forms, contact forms on other platforms
SpamKill analyzes visitor behavior — mouse movement, typing patterns, timing, device fingerprints — to determine whether a human or bot is submitting the form. Content doesn't matter.
• AI-written spam caught by behavioral signals
• Spam blocked before submission reaches your system
• Behavior-based — content alone never triggers a false positive
• Works on any platform, any form
• Protects lead gen forms, CRM forms, comments, reviews
These submissions read like genuine business inquiries — flawless grammar, real-sounding names, plausible emails. A content filter has nothing to flag. But SpamKill watches how each form was filled, not what was typed — so the bot gives itself away.
Content filtering catches spam that looks like yesterday's spam. The moment a bot writes a clean message, the words tell you nothing. Behavior is the one thing a bot can't fake — so behavior is what SpamKill reads.
SpamKill blocks spam before it enters your database with 99.9% accuracy and zero manual review needed. Akismet filters spam after it enters your database with about 90% accuracy, requiring you to manually review a spam folder. SpamKill protects all form types, while Akismet focuses primarily on comments.
On WordPress, through supported form plugins such as Contact Form 7, Jetpack, Gravity Forms and Fluent Forms, and only by reading what was typed. SpamKill protects all types of web forms, including contact forms, lead generation forms, signup forms and any custom HTML form, on any platform.
Yes, for comments and WooCommerce reviews. There is no personal-use clause, no key and no quota.
Both. The plugin is the connector; screening happens in SpamKill's cloud. Legitimate submissions are delivered to your site and discarded from our servers; details are in the plugin's External Services section.
No. Contact and lead-gen forms are the Pro tier, with a 30-day free trial.
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Block bots before they submit — not after they pollute your data.