RSyntaxTree

RSyntaxTree Version: 2.5.0

Thank you for using RSyntaxTree. If you like it, please give a star on GitHub. It will be a great encouragement for me 😃

About

RSyntaxTree is a graphical syntax tree generator written in the Ruby programming language.

Documentation of the input text syntax and markups of RSyntaxTree is available in English and Japanese. See also Example Gallery for different types of sample input and result syntree images.

A command-line version of RSyntaxTree is available on GitHub. A web user interface for RSyntaxTree is also available; you can run RSyntaxTree with a web UI locally on your computer using Docker.

The original version of RSyntaxTree was inspired by phpSyntaxTree by André Esenbach.

What's new

As of 2.5.0 (November 2026). Dates and details for every release are in the changelog.

Leaf align: the leaves on one row, by lowering the words or whole subtrees
Movement paths go around every label in their way, and above the words in bottom-to-top trees
Connectors from a short node start right below its label, even beside a taller one
\' keeps a straight apostrophe, \@ is an at sign, and \+ before digits is a plus sign
Every mistake at once: all errors listed with how to fix each, not just the first
Checking as you type: mistakes marked in the editor margin
JSON output renamed from lsif to json (lsif still works until 3.0)
Feature matrices in the JSON output as rows and cells
Shear: tilt the whole figure, with Plane behind shear drawing the plane behind it
Label air: the same space above and below every label
JPG and GIF output removed; use PNG
symmetrize, tidy_spacing and tidy_nest removed in favour of Tidy layout and H spacing
Derivations: one rule across each node's daughters, words at the top with Direction: btt
Attribute-value matrices: \t aligns columns and #( … #) nests matrices
One-page notation reference: notation.txt, also printed by rsyntaxtree --notation
Region shade with %: shade the whole subtree a node governs, in colour with %@blue:
Mirror option: right-to-left trees for Arabic and Hebrew syntax
Tidy layout: one scale from symmetric to high that packs the tree
Per-node colour with @color:, left-to-right layout with Direction, and an IPA virtual keyboard

How to cite

If you use RSyntaxTree in your research or teaching materials, please cite it. You can use the following BibTeX entry (adjust version to the one shown at the top of this page):

@software{hasebe_rsyntaxtree,
  author  = {Hasebe, Yoichiro},
  title   = {RSyntaxTree: A graphical syntax tree image generator},
  url     = {https://yohasebe.com/rsyntaxtree},
  doi     = {10.5281/zenodo.21916150},
  version = {1.9.0},
  year    = {2026}
}

Author

Yoichiro HASEBE

License