A broken external link is a link from your site to another site that no longer works. The page you refer to is gone or the site is offline.
Visitors who follow the link get an error and lose some trust in your page. For Google, a page full of dead references looks neglected.
Snaglist checks every outgoing link once. Links that return 400 or higher, or no answer, are listed with the page they are on. Codes that sites use to block automated visitors (401, 403, 405, 429 and 999, used by LinkedIn) are left out, because the link usually works for a person.
Snaglist runs this check and 43 others on every page of your site, every week. 14 days free, no credit card needed.
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