What are some alternatives?
When comparing MetaTagTools.com and SEO Tools Centre, you can also consider the following products
MetaTagsTool.com - Meta Tag Analyzer, Simulator, & Generator
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
OpenGraphTool.com - Open Graph Checker Tool
SEO PowerSuite - Get all SEO tools in one pack - download free edition of SEO PowerSuite and get top 10 rankings for your site on Google and other search engines!
OpenGraphTags - Open Graph Tag Simulator
Grammarly - Clear, effective, mistake-free writing everywhere you type.