Trilium Notes supports importing Markdown restricted to the CommonMark specification (where tables are not supported )

If you want to import just a chunk of markdown from clipboard, you can do it from editor block menu:

You can also import Markdown files from files:

• single markdown file (with .md extension)
• whole tree of markdown files (packaged into .zip archive)
  • Markdown files need to be packaged into ZIP archive because browser can't read directories, only single files.
  • You can use e.g. 7-zip to package directory of markdown files into the ZIP file

You can export whole subtree to ZIP archive which will have directory structured modelled after subtree structure:

If you want to export just single note without its subtree, you can do it from Note actions menu:

If you want to export protected notes, enter a protected session first! This will export the notes in an unencrypted form, so if you reimport into Trilium, make sure to re-protect these notes.