# seek-oss/capsize

Flipping how we define typography in CSS.

Repository: https://github.com/seek-oss/capsize
Canonical: https://ross.abutalabs.com/products/capsize
Homepage: https://seek-oss.github.io/capsize/
Language: TypeScript
License: MIT
License Family: permissive
Last push: 2026-08-12T05:11:30+00:00

## Health v2 (maintenance only)
Score: 96/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 97, release rhythm 93, longevity 100
- inputs: {"age_days": 2282, "days_push": 21, "days_rel": 45, "gap_med": 23, "n_releases_24m": 20}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1716, forks 47 (observed 2026-08-28T04:05:26.311959+00:00)

## What it is
Capsize is a TypeScript library that uses font metadata to make CSS text sizing and layout predictable, sizing text by cap height and trimming whitespace above capitals and below the baseline. It provides style generation APIs, a font metrics package, and integrations with CSS-in-JS tools like vanilla-extract.

## Use cases
- trim leading whitespace above capital letters in css text
- align text baselines across different fonts
- size typography by cap height instead of font size
- remove extra space below the text baseline
- generate css for predictable line height and leading
- integrate font metric based typography with css-in-js frameworks

## When to choose
- you need pixel-precise vertical text alignment in web layouts
- you want consistent spacing between text and adjacent elements
- you use vanilla-extract or css-in-js and want leading trim support

## When to avoid
- you only need simple typography without baseline trimming
- your project is not web/css based
- you cannot depend on font metrics for your fonts

## Facets
- artifact type: library
- maturity: active
- function: css-framework, ui-components, developer-tools
- domain: frontend, web-development, web-design
- platform: browser
- tags: typography, font-metrics, leading-trim, css-in-js, baseline-alignment, vanilla-extract, nodejs, web-server

## Member repositories
- seek-oss/capsize (main) score 96

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:26.311959+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:34:15.854978+00:00, confidence not recorded.
  - readme: https://github.com/seek-oss/capsize (fetched 2026-08-28T04:05:26.311959+00:00, sha 4f190eb7950e)
  - homepage: https://seek-oss.github.io/capsize/ (fetched 2026-08-29T11:10:40.035304+00:00, sha ebddc9a2230a)
  - registry_npm: https://registry.npmjs.org/capsize (fetched 2026-08-29T11:10:40.037829+00:00, sha 9d2cf656014b)
- Data as of 2026-08-30T08:39:29.467469+00:00.