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Invisible Anti-Spam & CAPTCHA — reCAPTCHA Alternative for All Forms

▲ 15 points • 9 comments • by MatthiasNordwig • 2w ago • HN discussion ↗

Pangram verdict · v3.3

We believe this text is mainly AI, with some human-written content.

99 %

AI likelihood · overall

AI
1% human-written 99% AI-generated
SEGMENTS · HUMAN 1 of 16
SEGMENTS · AI 15 of 16
WORD COUNT 1,418
PEAK AI % 100% · §2
Analyzed
Oct 22
backend: pangram/v3.3
Segments scanned
16 windows
avg 89 words each
Distribution
1 / 99%
human / AI fraction
Verdict
AI
Pangram v3.3

Article text · 1,418 words · 16 segments analyzed

Human AI-generated
§1 AI · 100%

Spam protection your visitors never see.

§2 AI · 100%

No image grids, no “I’m not a robot” checkbox, no puzzles, nothing to click. Your visitors just hit Send — while their browser silently solves a tiny cryptographic challenge (proof-of-work) in a few milliseconds.

§3 AI · 100%

Real humans never notice.

§4 AI · 100%

Mass-spam bots either fail the challenge or have to burn so much computing power per message that spamming your site stops being worth it.

§5 AI · 100%

Every form, out of the box.

§6 AI · 100%

WordPress logins, registrations and comments, WooCommerce checkout and reviews, and virtually every form plugin — Contact Form 7, Elementor Pro Forms, WPForms, Gravity Forms, Ninja Forms, Fluent Forms, Formidable and dozens more (full list below). One plugin protects all of them, and the most popular builders are detected and configured automatically on activation. Truly universal — not a list of integrations Most anti-spam tools protect only the form plugins they ship an integration for. If your builder is not on their list — or you use a hand-coded form, a theme’s built-in form, or three different builders on one site — you are on your own. This plugin works differently: it recognizes submissions by their signature — the characteristic fields and actions of the request itself — instead of hooking into specific form plugins. That is why it covers any form: Popular builders are recognized automatically: their signatures ship with the plugin and are pre-configured on activation. Everything else — custom-coded forms, exotic builders, legacy themes — you teach the spam check yourself in under a minute: turn on direct analysis mode, submit the form once, click save.

§7 AI · 100%

Done.

§8 AI · 100%

No code, no waiting for the developer to add your builder. And because no integration code is involved, nothing breaks when your form builder updates. In practice that solves two everyday problems: Real sites mix. A typical site has comments, a contact form from one builder, a newsletter signup from another, WooCommerce reviews — protecting each with its own anti-spam solution means more plugins, more settings pages, more things that can conflict. Here, one plugin covers the whole site. Designers and agencies standardize. If you build sites for clients, you can install the same proven plugin on every project — no matter which form stack the client uses (or switches to later). One tool to know, one place to look when something needs attention. Why “invisible” wins Every CAPTCHA interaction costs you real visitors: an extra click here, an unreadable image there, “select all traffic lights” on a phone screen — and the contact request or sale is gone. This plugin flips the deal: instead of making humans prove themselves, it makes the device pay. The visitor’s browser proves it is a real, JavaScript-running client by doing a moment of invisible computation. Zero friction for people, real costs for bots. Self-contained and featherweight Everything runs on your own web server — there is no external service in the loop. That is not just a privacy nicety, it is an operational one: Nothing external can fail. No third-party API whose outage, rate limit or latency silently breaks your forms. Your spam protection is exactly as available as your site. Nothing external slows you down. No remote scripts, no extra DNS lookups or connections — your PageSpeed and Core Web Vitals stay untouched.

§9 AI · 100%

Tiny footprint.

§10 AI · 100%

A few kilobytes of JavaScript and lean server code; runs fine on shared hosting, staging environments and even intranets without internet access. Why not just use … Google reCAPTCHA, hCaptcha or Turnstile? They require an account and API keys, load scripts from external servers (hello, consent banners) and still challenge real users when in doubt. This plugin needs no keys, loads no third-party scripts and never challenges anyone.

§11 AI · 100%

Akismet?

§12 AI · 100%

Sends the content of every submission to an external service for analysis, and commercial sites need a subscription. Here, everything stays on your own server. Honeypot fields and time checks? Modern bots skip honeypots routinely, and browser autofill loves to fill them by accident. Proof-of-work attacks the economics of spam instead of playing hide-and-seek. And they all share one structural limit: they protect the forms they ship an integration for. This plugin protects the forms you actually have (see “Truly universal” above). Key features Invisible — zero user interaction, ever Protects everything: logins, registrations, comments, WooCommerce, every form builder — even hand-coded custom forms No account, no API keys, no external service for the spam check — install and you are done Brute-force protection for logins, with optional Fail2Ban log support Adaptive under-attack mode: the challenge automatically gets harder for everyone while a spam wave is running, and relaxes afterwards Your choice per site: block spam, deliver it flagged, or just collect it in a spam inbox and watch Teach it live: unrecognized custom form? Direct analysis mode adds it with one click, straight from the live page Lightweight: a few KB of JavaScript, no render-blocking, no layout shift Privacy-friendly by design: no cookies, no sessions, no tracking, no visitor data leaves your server, IP addresses are only stored as hashes — GDPR/DSGVO/RGPD-friendly without a consent banner Free Setup Guide Works with Pre-configured out of the box — as soon as the plugin is active, these are recognized automatically, no setup: WordPress: Login, Password Reset, Comments WooCommerce: Checkout, Login, Password Reset, Product Reviews (the shopping cart is deliberately not checked) Form and page builders: Contact Form 7, WPForms, Elementor Pro Forms, Ninja Forms, Fluent Forms, Forminator, Gravity Forms, Formidable Forms, Everest Forms, WS Form, SureForms, MetForm, JetFormBuilder, Otter Blocks, Spectra, Kadence Blocks, Essential Blocks, Divi Forms, MW WP Form, Jetpack Forms, Mailchimp for WordPress, MailPoet, WP User Frontend, wpDiscuz, bbPress (topics & replies), Thrive Architect, Thrive Leads, Thrive Apprentice, Thrive Quiz Builder, Thrive Comments, UserFeedback, Popup Maker (subscription form), YITH WooCommerce Wishlist, Newsletter (subscription forms), CoBlocks, Popup Builder, Hustle, MailerLite, Email Subscribers, Quiz and Survey Master, WP-Polls, Form Maker, Gutena Forms, Happyforms, Brevo, Mailchimp List Subscribe, Calculated Fields Form, Crowdsignal Forms (NPS & feedback), Pirate Forms, Hostinger Reach, FormLayer, My Sticky Elements, Cool FormKit, Visual Form Builder, Royal Elementor Addons (forms), Happy Addons (Mailchimp form), Chaty (contact form), Jeg Kit (Mailchimp form), Element Pack Lite (contact form), Depicter (lead forms), Hello Plus (forms), PopupKit (subscription form) Reviews and testimonials: Customer Reviews for WooCommerce, Strong Testimonials, Site Reviews, WP Ultimate Review Checkout and registration forms (recognised and recorded; blocking them is a separate switch, off by default): BuddyPress (registration), WP-Members (registration), ProfilePress (registration & checkout), Easy Digital Downloads (checkout), CartFlows (checkout login), Amelia (booking), Bookly (booking) Added in under a minute, without code — switch on direct analysis mode, submit the form once, click save: registration forms (WordPress and WooCommerce), Ultimate Member, BuddyForms, MemberPress, Paid Memberships Pro, CheckoutWC & Flux Checkout, Quform, NEX-Forms, Bit Form, Form Maker, Funnelforms, Mailjet, SiteOrigin Page Builder, Calculated Fields Form, weForms, Responsive Contact Form Builder, Smart Forms, Kali Forms, Happyforms, ApplyOnline, FormCraft, CRM Perks Forms, Tripetto, Easy Form Builder, SimpleForm — and any hand-coded or custom form. One honest limit: a form that is hosted elsewhere and only embedded on your page (Typeform, Jotform, Zoho Forms, HubSpot, OptinMonster and the like) sends its data straight to that service. The submission never reaches WordPress, so no WordPress plugin — this one included — can check it. 6.2.0 Fixed: The repeat-sender lock no longer remembers numbers, so order, product, event or phone numbers lock out no one. Changed: The server now waits up to 5 seconds for a slow device to finish its check before rejecting a submission. Changed: The invisible check now starts once the page has loaded, so visitors who submit quickly are no longer rejected. Fixed: One rejected cart request could block other shoppers of the same product for 36 hours. Fixed: The Add to Cart button could be rejected as spam; WooCommerce cart requests are no longer checked. Fixed: Saving the settings broke rule lines with => or & (they were stored HTML-encoded); such lines are repaired on update. Fixed: Deleting the plugin failed with a fatal error and left its tables and settings behind. Fixed: Sites that already monitored a checkout or registration form keep blocking spam on it after this update.

§13 AI · 100%

Added: Out-of-the-box detection for Royal Elementor Addons, Happy Addons, Chaty, Jeg Kit and Element Pack Lite.

§14 Human · 6%

Added: Out-of-the-box detection for Depicter, Hello Plus, PopupKit and Strong Testimonials. Added: Out-of-the-box detection for Customer Reviews for WooCommerce, Site Reviews and WP Ultimate Review.

§15 AI · 100%

Added: Registration forms of BuddyPress, WP-Members and ProfilePress are recognised.

§16 AI · 100%

Added: Checkouts and bookings of EDD, ProfilePress, CartFlows, Amelia and Bookly are recognised.