Markdown is a plain text format for writing structured documents, based on conventions used for indicating formatting in email and usenet posts. It was developed in 2004 by John Gruber, who wrote the first markdown-to-html converter in Perl, and it soon became widely used in websites. by 2014 there were dozens of implementations in many languages.
John Gruber's canonical description of Markdown's syntax does not specify the syntax unambiguously.
In the absence of a spec, early implementers consulted the original
Markdown.pl code to resolve these ambiguities. But
Markdown.pl was quite buggy, and gave manifestly bad results in many cases, so it was not a satisfactory replacement for a spec.
Because there is no unambiguous spec, implementations have diverged considerably. As a result, users are often surprised to find that a document that renders one way on one system (say, a GitHub wiki) renders differently on another (say, converting to docbook using Pandoc). To make matters worse, because nothing in Markdown counts as a “syntax error,” the divergence often isn't discovered right away.
There's no standard test suite for Markdown; the unofficial MDTest is the closest thing we have. The only way to resolve Markdown ambiguities and inconsistencies is Babelmark, which compares the output of 20+ implementations of Markdown against each other to see if a consensus emerges.
We propose a standard, unambiguous syntax specification for Markdown, along with a suite of comprehensive tests to validate Markdown implementations against this specification. We believe this is necessary, even essential, for the future of Markdown.
That's what we call Standard Markdown.
This website was originally shut down after a complaint by John Gruber. Is no longer has any connection to the original authors and is being maintained just for posterity and curiosity.
This website was originally created by a group of Markdown fans who either work at companies with industrial scale deployments of Markdown, have written Markdown parsers, have extensive experience supporting Markdown with end users – or all of the above.
- John MacFarlane
- David Greenspan
- Vicent Marti
- Neil Williams
- Benjamin Dumke-von der Ehe
- Jeff Atwood
Read the spec, run the test suite, and exercise our reference implementations. Provide feedback!
Perhaps the best way to provide feedback is to implement your own Standard Markdown parser, as one of our major goals is to make Markdown easier to parse, and to eliminate the many old inconsistencies and ambiguities that made writing a Markdown parser so difficult. Did we succeed?
We'll operate standardmarkdown.com indefinitely as a central hub, with the following essential resources:
The official specification for Standard Markdown.
The official reference implementation and validation test suite on GitHub.
The official Discourse discussion area and mailing list.
The official dingus which allows people to experiment with Standard Markdown.
The current version of the Standard Markdown spec is complete (two years in the making!), but provisional pending public feedback, testing, and evaluation.
With your help, we plan to announce a finalized 1.0 spec and test suite in the next few months, along with implementations in many different languages.