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Captcha Tools

55 tools 73,731 sites Section: Build & Framework
Stackdar alerts

Get told when a new site picks a Captcha tool.

Stackdar watches every launch we detect and sends you the ones that ship with anything in Captcha, your competitors' tools included, by email, Slack or webhook. On every plan, from £15 a month.

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Source: All sites   All launches   Launch platforms   StackScope Discovery   StackScope Wider Web  

The most-adopted captcha tool we track is Cloudflare Turnstile (68,122 sites). We've detected 55 captcha tools across 73,731 public sites.

Captcha tools we've detected

Tool 90‑day Sites
Cloudflare Turnstile site ↗
Privacy-friendly CAPTCHA replacement.
68122
hCaptcha site ↗
Privacy-friendly bot-detection challenge service, marketed as a Google reCAPTCHA alternative.
5071
Friendly Captcha site ↗
Privacy-friendly, proof-of-work CAPTCHA alternative for forms.
251
TNcode
Open source slider puzzle captcha library for PHP and JavaScript forms.
175
DS CF7 Math Captcha site ↗
WordPress plugin that adds a math question captcha to Contact Form 7 forms to block spam submissions.
136
Cap (CAPTCHA) site ↗
Open-source proof-of-work CAPTCHA alternative using WebAssembly.
107
i13 reCaptcha site ↗
WordPress and WooCommerce plugin range from I13 Web Solution that adds Google reCAPTCHA to login, registration and checkout forms.
99
Simple Cloudflare Turnstile and reCAPTCHA for Contact Form 7
WordPress plugin that adds reCAPTCHA or Turnstile verification to Contact Form 7 forms.
90
CAPTCHA 4WP
WordPress plugin that adds Google reCAPTCHA and hCaptcha protection to site forms.
88
WP Captcha
WordPress plugin that adds captcha protection and brute force login defence.
72

Showing top 10 of 55 captcha tools by adoption. 45 more not shown.

The StackScope API serves every captcha tool and the launches using each, filterable and exportable, from £15 a month.

Launches using Captcha tools

Launch Launched Score
Sufuku Oct 16, 2026 10.0
YoovOh Oct 16, 2026 4.0
HomelessHelper Oct 16, 2026 10.0
Halocard Virtual Cards Oct 16, 2026 10.0
Grainform Oct 16, 2026 10.0
Foresiet Xtreme Oct 16, 2026 10.0

Often built with

Categories the captcha sites we track also commonly use:

Security (2611) DNS Provider (2561) SEO (2223) Analytics (2190) Framework (1953) CDN (1942)