Markdown checker
Paste a document and see what will render wrong before anyone else does. Every finding says what happens and links to the page explaining why.
- Breaksline 3checkbox-missing-space
A task list needs a space between the brackets: write - [ ] rather than - [].
Why this happens →- [] ship the converters - Breaksline 6table-missing-divider
A table needs a line of dashes under the header row, or it renders as lines with pipes in them.
Why this happens →| Feature | Status | - Probably wrongline 9single-trailing-space
One trailing space does nothing. Two make a line break, and a backslash is safer because editors strip trailing whitespace.
Why this happens →A line with one trailing space - Breaksline 12link-space
A link cannot have a space between ] and (. This renders as literal brackets.
Why this happens →[the docs] (https://example.com)
How it works
- The document is read line by line, tracking front matter and code fences, so a markdown sample inside a code block is never reported as a mistake.
- Findings are graded: breaking means it will not render as you meant, probably wrong means it usually is, and worth knowing is a difference that surprises people.
- Each finding carries the line number, the line itself, and a link to the knowledge-base page that explains the rule.
Questions
How is this different from markdownlint?
markdownlint enforces a style guide and reports rule numbers. This one only looks for things that render wrong or surprise you, and it explains each one in a sentence rather than pointing at a rule table.
Does it check my links resolve?
No. That would mean fetching every URL, which is a request per link and exactly the kind of thing this site does not do with your document. It checks that links are written correctly, not that they are alive.
My document is clean but something still renders wrong.
Then it is likely a difference between renderers rather than a mistake. The platform tables in the knowledge base cover where GitHub, Discord, Slack and Obsidian disagree.