Real quotation marks, dashes and spaces, in 26 languages.

A library that fixes the typography of running text. Give it a string and a language. It gives the string back with the right quotation marks, dashes where there were hyphens, an ellipsis, and no-break spaces where a line should not break.

bun add git+ssh://git@github.com/mokhniuk/typography.git#v0.13.0

Read the docs Try it in the playground

The engine is one function over a string. Everything else is a way of getting your text into it, or a way of seeing what it did.

Every format your text lives in

Plain text, an HTML string, a Markdown document, a rehype or hast tree, React components, and a command line for files and CI. One engine under all of them. For the browser, a DOM entry hangs the punctuation and checks which characters the page’s font can draw. The API

A pack per language, and no default rule that names one

Quotation marks and how they nest, the dash, the spacing habits, the one-letter words that may not end a line: each is data in a language pack, which is why adding a language is one pack file. Two opt-in rules still have a case for one language: the space before French punctuation, and the English temperature labels of the degree sign. The languages

Two registers

Display text is the default: interfaces, marketing, event pages. The literary register sets book-like text, and so far only English has one: British quotes, “…” with “…” inside, and a spaced en dash. A dash for a line of dialogue is set in both registers, where the language writes dialogue that way.

It tells you what it changed

explain returns every change with the rule that made it and the text before and after, so a surprise is a question with an answer, not a mystery. The rules

Hanging punctuation, measured

An opening mark hangs into the left margin so the first letter lines up with the lines under it, and a closing mark hangs into the right. Each mark’s width is measured in the browser once, and again when the web fonts load. Line breaks are never measured. How it works

It knows what your font cannot draw

A rule that would insert a character the font has no glyph for leaves that stretch of text as you typed it, and the rest of the line is still set: better a straight quote than a box. A quotation keeps both its marks or neither. In React the list fills itself from the page’s own font (TypographyRoot, avoidMissing); …/dom exposes the measure. The font checker

Safe on what is not prose

Web addresses, emails and code spans come back byte for byte; tags, attributes and the contents of pre and code are never touched. An unknown rule name throws instead of passing quietly.

Proved, not promised

Property tests on seeded random text in every language: no letter or digit is lost or added, and a second pass changes nothing. A differential harness proves a speed change rewrote no output. Known limits

Each language has its own pack: its quotation marks and how they nest, its dash, its habits with spaces. These four are not translations of one sentence; each is written the way that language is.

22 rules run by default, and 11 more you switch on. Here are some of them on one line each. A boxed space is a no-break space.

All 33 rules, with their reasons

One function takes a string and a language. The other entry points do the same for plain text, HTML, Markdown, rehype trees and React, and bring the browser side: hanging punctuation and font checks.

import { typographic, explain } from '@mokhniuk/typography';

typographic('He said "we\'re here" - and left.', 'en', { quoteStyle: 'us' });
// He said “we’re here” — and left.  (a no-break space before the dash)

explain('He said "hi"... 21-26', 'en', { quoteStyle: 'us' }).changes;
// quote “ · quote ” · ellipsis … · dash.range –

The API reference

Before you depend on it, you should know where it is weak.

• No language has been read by a native speaker. Twenty packs follow published style guides, and some of those we could only read in part. English, Ukrainian, German, Polish, French and Swiss German come from general knowledge. Each language page lists what it was written from.
• Where the engine and Unicode’s CLDR disagree about quotation marks (English, German, French, Swiss German), the decision record says so, instead of choosing quietly.
• English sets “” by default. That is this project’s house style. Pass quoteStyle: 'us' for “”.
• Some input can’t be read with certainty. An inch mark inside a quotation ("a 5" hole") is one: the engine closes the quotation early, at the inch mark. Such cases are listed in the known limits.

Known limits · Languages and their review status

Where each decision came from, and what a reader should know about the marks themselves. Written while building the engine.

1. October 22, 2026 · 3 min read

   Typing typographic characters on Windows

   Alt codes on the numeric keypad, the Win + . symbol panel, and Word’s own shortcuts — three ways to type every dash, quote and sign, with the full code table.

2. October 22, 2026 · 3 min read

   Why typographic correction is hard to automate

   Replacing straight quotes with curly ones looks like a dozen regexes. Here is what the dozen regexes get wrong, and what an engine has to do instead.

3. October 22, 2026 · 3 min read

   The no-break space does the quiet work

   The most useful typographic character is invisible. Where a no-break space belongs, why CSS cannot place it for you, and the rules that set it.

All the articles

Typography Engine is a solo project by Oleg Mokhniuk: the rules, the language packs, the docs and this site are one person’s work.

If it is useful and you want to give something back, skip the coffee. The best way to support this project is a donation to Come Back Alive, the Ukrainian foundation that equips the people defending Ukraine.

Donate to Come Back Alive

Or support the author directly: paypal.me/mokhniuk.