# @capsizecss/unpack > Unpack capsize font metrics from fonts Latest version **4.0.1** (published 2026-06-12) · MIT license · 0 weekly downloads ## Install ```sh npm install @capsizecss/unpack pnpm add @capsizecss/unpack yarn add @capsizecss/unpack bun add @capsizecss/unpack ``` ## Health **Score 65/100 (B)** — status: active. Positive: has types; esm support; no vulnerabilities; has provenance; high maintenance score. Warnings: low downloads. ## Facts | | | |---|---| | Version | 4.0.1 | | Published | 2026-06-12 | | First published | 2021-09-24 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | bundled | | Module format | ESM + CommonJS | | Node | >=18 | | Dependencies | 1 | | Unpacked size | 18.9 KB | | Known vulnerabilities | 0 | | Install scripts | no | | Provenance | attested (GitHub Actions) | | GitHub stars | 1719 | | Author | Michael Taranto | | Maintainers | mjt01, seek-oss-ci | | Keywords | capsize, leading trim, white space, baseline, basekick, cap height, typography, line gap, leading | ## Links - npm: https://www.npmjs.com/package/@capsizecss/unpack - Repository: https://github.com/seek-oss/capsize - Homepage: https://github.com/seek-oss/capsize#readme - Issues: https://github.com/seek-oss/capsize/issues - npm.io page: https://npm.io/package/@capsizecss/unpack ## Dependencies (1) - [fontkitten](https://npm.io/package/fontkitten.md) ^1.0.3 ## Alternatives - [d3-force-3d](https://npm.io/package/d3-force-3d.md) — 1.0M weekly downloads - [ng2-charts](https://npm.io/package/ng2-charts.md) — 486.8K weekly downloads - [@arcgis/core](https://npm.io/package/@arcgis/core.md) — 257.8K weekly downloads - [react-sparklines](https://npm.io/package/react-sparklines.md) — 249.3K weekly downloads - [react-native-gifted-charts](https://npm.io/package/react-native-gifted-charts.md) — 182.3K weekly downloads ## Recent versions - 4.0.1 (latest) — 2026-06-12 - 0.0.0-test-20251006235016 (test) — 2025-10-06 - 0.0.0-add-weight-italic-support-20240507015549 (add-weight-italic-support) — 2024-05-07 - 0.0.0-metrics-xwidthavg-inc-space-20240305000813 (metrics-xwidthavg-inc-space) — 2024-03-05 - 0.0.0-add-subset-support-20240304225850 (add-subset-support) — 2024-03-04 - 0.0.0-metrics-frequency-data-20240215031405 (metrics-frequency-data) — 2024-02-15 - 0.0.0-master-20240214212615 (master) — 2024-02-14 - 0.0.0-crackle-20240208083429 (crackle) — 2024-02-08 - 0.0.0-add-language-support-v2-20231129052138 (add-language-support-v2) — 2023-11-29 - 0.0.0-add-language-support-20231121023926 (add-language-support) — 2023-11-21 - 0.0.0-x-width-avg-20230123213508 (x-width-avg) — 2023-01-23 - 0.0.0-x-avg-char-width-20221118004523 (x-avg-char-width) — 2022-11-18 - 0.0.0-createfontstack-20221110224822 (createfontstack) — 2022-11-10 - 4.0.0 — 2025-12-18 - 3.0.1 — 2025-11-12 - … 23 more at https://npm.io/package/@capsizecss/unpack/versions ## README Capsize
# @capsizecss/unpack Unpack the capsize font metrics directly from a font file. ```bash npm install @capsizecss/unpack ``` - [Usage](#usage) - [fromBuffer](#frombuffer) - [fromBlob](#fromblob) - [fromUrl](#fromurl) - [fromFile](#fromfile) - [Options](#options) - [postscriptName](#postscriptname) - [Font Metrics](#font-metrics) ## Usage ### `fromBuffer` Takes a buffer and returns the resolved [font metrics](#font-metrics). ```ts import { fromBuffer } from '@capsizecss/unpack'; const metrics = await fromBuffer(buffer); ``` ### `fromBlob` Takes a file blob and returns the resolved [font metrics](#font-metrics). ```ts import { fromBlob } from '@capsizecss/unpack'; const metrics = await fromBlob(file); ``` ### `fromUrl` Takes a url string and returns the resolved [font metrics](#font-metrics). ```ts import { fromUrl } from '@capsizecss/unpack'; const metrics = await fromUrl(url); ``` ### `fromFile` Takes a file path string and returns the resolved [font metrics](#font-metrics). ```ts import { fromFile } from '@capsizecss/unpack/fs'; const metrics = await fromFile(filePath); ``` ## Options All of the above APIs accept an optional second parameter with the following options: #### `postscriptName` Capsize can extract the metrics for a single font from a TrueType Collection (TTC) file by providing the `postscriptName`. ```ts import { fromFile } from '@capsizecss/unpack'; const metrics = await fromFile('AvenirNext.ttc', { postscriptName: 'AvenirNext-Bold', }); ``` ## Font metrics The font metrics object returned contains the following properties: | Property | Type | Description | | -------------- | ------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | familyName | string | The font’s family name as authored by font creator | | fullName | string | The font’s full name as authored by font creator | | postscriptName | string | The font’s unique PostScript name as authored by font creator | | category | string | The style of the font: serif, sans-serif, monospace, display, or handwriting. | | capHeight | number | The height of capital letters above the baseline | | ascent | number | The height of the ascenders above baseline | | descent | number | The descent of the descenders below baseline | | lineGap | number | The amount of space included between lines | | unitsPerEm | number | The size of the font’s internal coordinate grid | | xHeight | number | The height of the main body of lower case letters above baseline | | xWidthAvg | number | The average width of character glyphs in the font for the selected unicode subset. Calculated [based on character frequencies in written text], falling back to the built in `xAvgCharWidth` from the OS/2 table. | | subsets | {
[subset]: { xWidthAvg: number }
} | A lookup of the `xWidthAvg` metric by subset (see [supported subsets]) | [based on character frequencies in written text]: ../metrics/README.md#how-xwidthavg-is-calculated [supported subsets]: ../metrics/README.md#subsets ## Thanks - [Devon Govett](https://github.com/devongovett) for creating [Fontkit](https://github.com/foliojs/fontkit). A [fork of Fontkit](https://github.com/delucis/fontkitten) does all the heavy lifting of extracting the font metrics under the covers. - [SEEK](https://au.seek.com) for giving us the space to do interesting work. ## License MIT. --- _Source: https://npm.io/package/@capsizecss/unpack · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._