Linebreaker: Intelligent Line Breaking for Markdown

Wed, 05 Nov 2025 00:00:00 +0000

Semantic Line Breaking for Markdown

Semantic Line Breaking for Markdown

A feature of markdown (Quarto) is that it ignores line breaks. A line break is just a space. (A double line break is a new paragraph).

Also it is a good practice to not have endless long lines in markdown files. Because if you put 3 sentence on one line and you make one change in one word git would change the whole line. But on the other hand you do not want to break a sentence at random places just that it fits to a 60-80 character line length.

Mattt developed the idea of semantic line breaks, where you break lines at meaningful places in the semantic logic of the sentence. I find the concept very convincing. Now with semantic linebreaks the markdown text is almost better readable than the rendered pdf or html without the line breaks.

To break lines automatically according to semantic line breaks I one would need a tool that understands natural language.

And they did, sembr, but for me it screwed up my quarto markdown files.

So what I did is to create a simpler rule based line braker that works well with markdown and even quarto files.

Hope it helps you with writing!

Features

Linebreaker provides intelligent line breaking for Markdown and text files with sophisticated handling of:

Smart Punctuation Handling

Citations: Preserves [@...] format citations (DOIs contain punctuation)
Numbers: Keeps decimal numbers intact (e.g., 3.14, 1,000.50)
Abbreviations: Recognizes common abbreviations (Dr., Prof., vs., et al., etc.)

Intelligent Breaking

Semantic breaks: Splits at conjunctions, commas, and logical connectors
Length-aware: Skips breaking sentences that are already short
Context-aware: Handles parentheses and brackets appropriately

Markdown-Aware

YAML headers: Skips frontmatter blocks
Code blocks: Preserves all code content unchanged

Installation

Install from PyPI using pip:

pip install linebreaker

Or using pixi:

pixi add --pypi linebreaker