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<spanclass=toggle-dark><svgxmlns="http://www.w3.org/2000/svg"width="20"height="20"viewBox="0 0 24 24"fill="none"stroke="currentcolor"stroke-width="2"stroke-linecap="round"stroke-linejoin="round"class="feather feather-moon"><pathd="M21 12.79A9 9 0 1111.21 3 7 7 0 0021 12.79z"/></svg></span><spanclass=toggle-light><svgxmlns="http://www.w3.org/2000/svg"width="20"height="20"viewBox="0 0 24 24"fill="none"stroke="currentcolor"stroke-width="2"stroke-linecap="round"stroke-linejoin="round"class="feather feather-sun"><circlecx="12"cy="12"r="5"/><linex1="12"y1="1"x2="12"y2="3"/><linex1="12"y1="21"x2="12"y2="23"/><linex1="4.22"y1="4.22"x2="5.64"y2="5.64"/><linex1="18.36"y1="18.36"x2="19.78"y2="19.78"/><linex1="1"y1="12"x2="3"y2="12"/><linex1="21"y1="12"x2="23"y2="12"/><linex1="4.22"y1="19.78"x2="5.64"y2="18.36"/><linex1="18.36"y1="5.64"x2="19.78"y2="4.22"/></svg></span></button><ulclass="navbar-nav social-nav order-3 order-md-5"><liclass=nav-item><aclass=nav-linkhref=https://github.com/mCaptcha><svgxmlns="http://www.w3.org/2000/svg"width="20"height="20"viewBox="0 0 24 24"fill="none"stroke="currentcolor"stroke-width="2"stroke-linecap="round"stroke-linejoin="round"class="feather feather-github"><pathd="M9 19c-5 1.5-5-2.5-7-3m14 6v-3.87a3.37 3.37.0 00-.94-2.61c3.14-.35 6.44-1.54 6.44-7A5.44 5.44.0 0020 4.77 5.07 5.07.0 0019.91 1S18.73.65 16 2.48a13.38 13.38.0 00-7 0C6.27.65 5.09 1 5.09 1A5.07 5.07.0 005 4.77 5.44 5.44.0 003.5 8.55c0 5.42 3.3 6.61 6.44 7A3.37 3.37.0 009 18.13V22"/></svg><spanclass="ms-2 visually-hidden">GitHub</span></a></li></ul><divclass="collapse navbar-collapse order-4 order-md-1"><ulclass="navbar-nav main-nav me-auto order-5 order-md-2"><liclass=nav-item><aclass=nav-linkhref=/about/>About</a></li><liclass=nav-item><aclass=nav-linkhref=/blog/>Blog</a></li><liclass=nav-item><aclass=nav-linkhref=/community/>Community</a></li><liclass=nav-item><aclass=nav-linkhref=/contact/>Contact</a></li><liclass=nav-item><aclass=nav-linkhref=/docs/prologue/introduction/>Docs</a></li></ul><divclass="break order-6 d-md-none"></div><formclass="navbar-form flex-grow-1 order-7 order-md-3"><inputid=userinputclass="form-control is-search"type=searchplaceholder="Search docs..."aria-label="Search docs..."autocomplete=off><divid=suggestionsclass="shadow bg-white rounded"></div></form></div></div></header><divclass="wrap container"role=document><divclass=content><sectionclass="section container-fluid mt-n3 pb-3"><divclass="row justify-content-center"><divclass="col-lg-12 text-center"><h1class=mt-0>Defend Like Castles</h1></div><divclass="col-lg-9 col-xl-8 text-center"><pclass=lead>mCaptcha is proof-of-work based captcha system that is privacy focussed and fully automated.</p><aclass="btn btn-primary btn-lg px-4 mb-2"href=/docs/prologue/introduction/role=button>Get started</a><pclass=meta>Libre software <ahref=https://github.com/mCaptcha>GitHub</a></p></div></div></section></div></div><sectionclass="section section-sm"><divclass=container><divclass="row justify-content-center text-center"><divclass=col-lg-5><h2class=h4>Privacy focused</h2><p>Doesn't track, doesn't profile your users.</p></div><divclass=col-lg-5><h2class=h4>Robust and Accurate</h2><p>Got users behind <ahref=https://en.wikipedia.org/wiki/Network_address_translation>NATs</a>? No issues. We don't use IP address for rate-liming. NAT or not you get the mCaptcha experience.</div><divclass=col-lg-5><h2class=h4>Best-in-class UX</h2><p>mCaptcha is silent, so silent that your users won't even feel it. No more anoying imgaes, no more helping for Big Brothers with their ML stuff</p></div></div><divclass="row justify-content-center text-center"><divclass=col-lg-5><h2class=h4>Defend like castles</h2><p>Our <ahref=https://en.wikipedia.org/wiki/Proof_of_work>PoW</a>-based solution defends fiersly. mCaptcha makes attacking your site more experience than what it will take for you to respond to the attacker's requests</p></div><divclass=col-lg-5><h2class=h4>Libre Soft
