RSyntaxTree is a graphical syntax tree generator for linguistic research.
Web App · Example Gallery · Documentation
RSyntaxTree provides a rich set of features for creating publication-quality syntax trees:
Use bracket notation to define tree structures:
[S [NP the cat] [VP [V sleeps]]]
Apply various text styles to node labels:
- Bold:
**text** - Italic:
*text* - Subscript:
_text_ - Superscript:
__text__ - Overline/Underline/Strikethrough:
=text=,-text-,~text~
Apply custom colors to individual nodes using @color: syntax:
[S [@red:NP the cat] [@blue:VP sleeps]]
Supports named colors (red, blue, green, etc.) and hex colors (@#FF5733:).
- Brackets:
[#NP text]→ draws brackets around the node - Rectangle:
[##NP text]→ draws a rectangle around the node - Triangle:
[^NP the quick fox]→ draws a triangle connector
Combine with colors: [#@red:NP text], [^@blue:VP phrase]
Connect nodes with lines or arrows:
[S [NP+1 text] [VP [V+>1 connects]]]
Generate trees in PNG, SVG, PDF, JPG, or GIF format.
A working web interface is available at https://yohasebe.com/rsyntaxtree.
You can also run RSyntaxTree's web interface on your local machine using Docker Desktop. See RSyntaxTree Web UI.
See RSyntaxTree Example Gallery for examples covering:
- Generative Grammar
- Combinatory Categorial Grammar
- Head-Driven Phrase Structure Grammar
- Cognitive Grammar
- Construction Grammar
- Pragmatics
- Phonology
- and more
Input text
[S
[NP |R|<>SyntaxTree]
[VP
[V generates]
[NP
[Adj #\+multilingual\
\+beautiful]
[NP syntax\
trees]
]
]
]
Output (PNG or SVG)
gem install rsyntaxtreeImportant for macOS users: If you encounter build errors for native extensions (gobject-introspection, cairo-gobject, gio2), run the following commands before installing RSyntaxTree:
gem install gobject-introspection -- --with-ldflags="-Wl,-undefined,dynamic_lookup"
gem install cairo-gobject -- --with-ldflags="-Wl,-undefined,dynamic_lookup"
gem install gio2 -- --with-ldflags="-Wl,-undefined,dynamic_lookup"Then install RSyntaxTree:
gem install rsyntaxtreeAlternatively, use the Docker image or the web interface.
Usage:
1) rsyntaxtree [options] "[S [NP text] [VP here]]"
2) rsyntaxtree [options] "(S (NP text) (VP here))" # Penn Treebank format
3) rsyntaxtree [options] "/path/to/text/file"
4) echo "[S [NP text] [VP here]]" | rsyntaxtree [options]
| Option | Description | Default |
|---|---|---|
-o, --outdir |
Output directory | ./ |
-f, --format |
Output format: png, gif, jpg, pdf, svg | png |
-l, --leafstyle |
Leaf style: auto, triangle, bar, nothing | auto |
-n, --fontstyle |
Font style: sans, serif, cjk, mono | sans |
-s, --fontsize |
Font size: 8-26 | 16 |
-c, --color |
Color mode: modern, traditional, off | modern |
-y, --symmetrize |
Symmetrical tree: on, off | off |
-p, --polyline |
Polyline connectors: on, off | off |
Run rsyntaxtree -h for the full list of options.
- Bracket notation:
[S [NP text] [VP here]] - Penn Treebank format:
(S (NP text) (VP here))- automatically converted - Standard input:
echo "[S [NP text]]" | rsyntaxtree
RSyntaxTree supports configuration files (.rsyntaxtreerc) in YAML format. Place the file in your home directory or current working directory.
# ~/.rsyntaxtreerc
format: svg
color: modern
fontsize: 18CLI options override config file settings.
For detailed documentation on syntax and markup:
Please use the following BibTeX entry when citing RSyntaxTree:
@misc{rsyntaxtree,
author = {Yoichiro Hasebe},
title = {RSyntaxTree: A graphical syntax tree image generator},
url = {https://yohasebe.com/rsyntaxtree},
year = {2026}
}Yoichiro Hasebe ([email protected])
RSyntaxTree is distributed under the MIT License.
