What are some alternatives?
When comparing Open Site Explorer and Pro Rank Tracker, you can also consider the following products
Majestic - Majestic - Link intelligence tools for SEO and Internet PR and Marketing. Site Explorer shows inbound link and site summary data.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Screaming Frog - Screaming Frog is search engine marketing agency offering search engine optimisation and pay-per-click advertising services.
Raven - Use Raven to create fully scalable vector art appropriate for logos or tee shirt designs.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
SEOmator - SEO website analysis & audit tool