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HSArticle Math CAPTCHA for Forms adds a math CAPTCHA to any WordPress form. No API keys. No third-party services. No configuration needed to get started.
Features:
- Math CAPTCHA — addition, subtraction, multiplication with sensible number ranges
- Two display modes: distorted canvas image (bot-resistant) or plain text (accessible)
- Server-side validation — answer stored in PHP session with HMAC signature, never exposed to the client
- Honeypot field — silent bot trap alongside the math challenge
- Rate limiting — blocks IPs after 10 failed attempts per 10 minutes
- Refresh button — generate a new question without reloading
- WPForms auto inject — protect any WPForms (free or pro) without adding a shortcode
- Registered as a CF7 form tag — no unknown tag warnings in the CF7 editor
- Session only starts on pages that actually contain a form — no impact on page caching elsewhere
- Clean admin page under its own menu — not buried under Settings
Supported form plugins:
- Contact Form 7
- WPForms (Free and Pro)
- Any HTML form via the [hs_mcf_captcha] shortcode
Plugin Details
Active Installs
20Total Downloads
298Version
1.0.1Requires WP
5.5Requires PHP
7.4Tested Up To
7.1Added
2026-06-20Last Updated
2026-09-15 5:18am GMTRatings
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