I am probably misunderstanding your requirements but if you are looking for something like regex101 then https://omrelli.ug/nearley-playground/ and https://bnfparser.firebaseapp.com/ although not sure how much 'practical' are they. Googling gives [2], [3], [4].

[2] https://mingodad.github.io/parsertl-playground/playground/ not sure.

[3] https://chrishixon.github.io/chpeg/playground/

[4] https://mdkrajnak.github.io/ebnftest/

If you use something like Antlr (https://www.antlr.org/) it has visualization tools and an online tester (http://lab.antlr.org/). There are also tools for visualizing generic EBNF grammars like this: https://jacquev6.github.io/DrawGrammar/