DNS propagation checker

You published the record, it resolves for you, and someone across the world still sees the old value. This reads the same name from six vantage points at once — five machines on separate continents plus our own resolver — through several public resolvers each, and shows you the whole grid. Give it the value you expect and every cell becomes a match or a mismatch; leave that blank and it reports whether the vantage points agree. The name is used exactly as you type it: www. is not stripped, and _dmarc.example.com works.