What are some alternatives?
When comparing OpenGraphTags and Open Site Explorer, you can also consider the following products
OpenGraphTool.com - Open Graph Checker Tool
Majestic - Majestic - Link intelligence tools for SEO and Internet PR and Marketing. Site Explorer shows inbound link and site summary data.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
MetaTagsTool.com - Meta Tag Analyzer, Simulator, & Generator
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
MetaTagTool.com - Meta Tag & Open Graph Tag Generator, Simulator, & Analyzer