SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Xenu's Link Sleuth - Xenus Link Sleuth checks Web sites for broken links.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
Integrity - Feature comparison of link checkers for Mac: Integrity, Integrity Plus and Scrutiny
Website Checker Tech - WebsiteChecker.Tech is SaaS tool that detects SEO and availability issues of your website, making it easier for you to fix them.
DRKSpiderJava - DRKSpider is an open source website crawler (sitemap generator) and link checker. Features: