# Free alternatives to Calibri

Calibri is a commercial humanist sans from Microsoft (Lucas de Groot) (https://learn.microsoft.com/en-us/typography/font-list/calibri). Bundled with Windows/Office under those EULAs; not licensed for web embedding. The name is used only to identify the typeface; BrandSweets does not host or embed it. Below: the 8 closest free, open-licensed families, ranked by a published deterministic score (https://brandsweets.com/fonts/alternatives/methodology).

## Reference profile

- Slug: `calibri`
- Category: sans · Class: humanist, rounded
- Traits: friendly, neutral, clean, rounded, monoline
- Roles: body, ui
- Metrics: x-height 0.47, cap height 0.64, normal width, low contrast (approximate, publicly documented)
- Languages: latin, latin-ext, cyrillic, greek · Variable: no
- Page: https://brandsweets.com/fonts/alternatives/calibri

## Score

`score = 0.35·classification + 0.25·metrics + 0.20·traits + 0.10·useCase + 0.05·language + 0.05·variable`; every axis in [0, 1]. A family gate runs first: specialist families (blackletter, script, glyphic, stencil, monospace, pixel) only list same-family fonts; elsewhere a cross-family mismatch is capped at 0.2. Curated picks are listed first, then pure formula; ties break on popularity, then slug.

## Ranked alternatives

### 1. Carlito — 86% (curated)

- Slug: `carlito` · sans · OFL-1.1 · static
- Page: https://brandsweets.com/fonts/carlito · font.md: https://brandsweets.com/fonts/carlito/font.md
- Why (curated): Metric-compatible with Calibri — identical widths, so documents don't reflow.
- Classification (×0.35): 1.00 — Same class: humanist, rounded.
- Metrics (×0.25): 0.98 — x-height 0.48 vs 0.47 for Calibri (near-identical); cap height 0.64 vs 0.64 for Calibri (near-identical); both normal width; both low stroke contrast.
- Traits (×0.20): 0.50 — Shares friendly, monoline, rounded (3 of 6 traits).
- Role (×0.10): 0.67 — Both suit body, ui.
- Language (×0.05): 1.00 — Covers all of Calibri's subsets (cyrillic, greek, latin, latin-ext).
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 2. Open Sans — 82% (curated)

- Slug: `open-sans` · sans · OFL-1.1 · Steve Matteson · static
- Page: https://brandsweets.com/fonts/open-sans · font.md: https://brandsweets.com/fonts/open-sans/font.md
- Why (curated): Humanist with Calibri's friendly rounded feel and generous x-height.
- Classification (×0.35): 1.00 — Same class: humanist.
- Metrics (×0.25): 0.68 — x-height 0.54 vs 0.47 for Calibri (noticeably different); cap height 0.71 vs 0.64 for Calibri (noticeably different); both normal width; both low stroke contrast.
- Traits (×0.20): 0.50 — Shares friendly, monoline, neutral (3 of 6 traits).
- Role (×0.10): 1.00 — Both suit body, ui.
- Language (×0.05): 1.00 — Covers all of Calibri's subsets (cyrillic, greek, latin, latin-ext).
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 3. Source Sans 3 — 85%

- Slug: `source-sans-3` · sans · OFL-1.1 · Paul D. Hunt · static
- Page: https://brandsweets.com/fonts/source-sans-3 · font.md: https://brandsweets.com/fonts/source-sans-3/font.md
- Classification (×0.35): 1.00 — Same class: humanist.
- Metrics (×0.25): 0.92 — x-height 0.49 vs 0.47 for Calibri (near-identical); cap height 0.66 vs 0.64 for Calibri (close); both normal width; both low stroke contrast.
- Traits (×0.20): 0.50 — Shares clean, monoline, neutral (3 of 6 traits).
- Role (×0.10): 0.67 — Both suit body, ui.
- Language (×0.05): 1.00 — Covers all of Calibri's subsets (cyrillic, greek, latin, latin-ext).
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 4. Zen Maru Gothic — 84%

- Slug: `zen-maru-gothic` · sans · OFL-1.1 · Yoshimichi Ohira · static
- Page: https://brandsweets.com/fonts/zen-maru-gothic · font.md: https://brandsweets.com/fonts/zen-maru-gothic/font.md
- Classification (×0.35): 1.00 — Same class: rounded.
- Metrics (×0.25): 0.83 — x-height 0.48 vs 0.47 for Calibri (near-identical); cap height 0.70 vs 0.64 for Calibri (noticeably different); both normal width; both low stroke contrast.
- Traits (×0.20): 0.60 — Shares friendly, monoline, rounded (3 of 5 traits).
- Role (×0.10): 0.67 — Both suit body, ui.
- Language (×0.05): 1.00 — Covers all of Calibri's subsets (cyrillic, greek, latin, latin-ext).
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 5. Nunito Sans — 82%

- Slug: `nunito-sans` · sans · OFL-1.1 · Vernon Adams, Jacques Le Bailly, Manvel Shmavonyan, Alexei Vanyashin · static
- Page: https://brandsweets.com/fonts/nunito-sans · font.md: https://brandsweets.com/fonts/nunito-sans/font.md
- Classification (×0.35): 1.00 — Same class: humanist.
- Metrics (×0.25): 0.80 — x-height 0.49 vs 0.47 for Calibri (near-identical); cap height 0.70 vs 0.64 for Calibri (noticeably different); both normal width; both low stroke contrast.
- Traits (×0.20): 0.43 — Shares clean, friendly, monoline (3 of 7 traits).
- Role (×0.10): 1.00 — Both suit body, ui.
- Language (×0.05): 0.75 — Covers cyrillic, latin, latin-ext; lacks greek.
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 6. Paytone One — 82%

- Slug: `paytone-one` · sans · OFL-1.1 · Vernon Adams · static
- Page: https://brandsweets.com/fonts/paytone-one · font.md: https://brandsweets.com/fonts/paytone-one/font.md
- Classification (×0.35): 1.00 — Same class: rounded.
- Metrics (×0.25): 0.82 — x-height 0.50 vs 0.47 for Calibri (close); cap height 0.69 vs 0.64 for Calibri (close); both normal width; both low stroke contrast.
- Traits (×0.20): 0.60 — Shares friendly, monoline, rounded (3 of 5 traits).
- Role (×0.10): 0.67 — Both suit body, ui.
- Language (×0.05): 0.50 — Covers latin, latin-ext; lacks cyrillic, greek.
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 7. Red Hat Text — 81%

- Slug: `red-hat-text` · sans · OFL-1.1 · MCKL · static
- Page: https://brandsweets.com/fonts/red-hat-text · font.md: https://brandsweets.com/fonts/red-hat-text/font.md
- Classification (×0.35): 1.00 — Same class: humanist.
- Metrics (×0.25): 0.81 — x-height 0.49 vs 0.47 for Calibri (near-identical); cap height 0.70 vs 0.64 for Calibri (noticeably different); both normal width; both low stroke contrast.
- Traits (×0.20): 0.43 — Shares clean, monoline, neutral (3 of 7 traits).
- Role (×0.10): 1.00 — Both suit body, ui.
- Language (×0.05): 0.50 — Covers latin, latin-ext; lacks cyrillic, greek.
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

### 8. Fredoka — 81%

- Slug: `fredoka` · sans · OFL-1.1 · Milena Brandão, Hafontia · static
- Page: https://brandsweets.com/fonts/fredoka · font.md: https://brandsweets.com/fonts/fredoka/font.md
- Classification (×0.35): 1.00 — Same class: rounded.
- Metrics (×0.25): 0.79 — x-height 0.50 vs 0.47 for Calibri (close); cap height 0.70 vs 0.64 for Calibri (noticeably different); both normal width; both low stroke contrast.
- Traits (×0.20): 0.60 — Shares friendly, monoline, rounded (3 of 5 traits).
- Role (×0.10): 0.67 — Both suit body, ui.
- Language (×0.05): 0.50 — Covers latin, latin-ext; lacks cyrillic, greek.
- Variable (×0.05): 1.00 — Static instances, like Calibri.
- Family gate: pass — Same family: sans.

## Self-host Carlito (woff2)

- 400 normal: https://fonts.brandsweets.com/carlito/carlito-400.woff2
- 400 italic: https://fonts.brandsweets.com/carlito/carlito-400i.woff2
- 700 normal: https://fonts.brandsweets.com/carlito/carlito-700.woff2
- 700 italic: https://fonts.brandsweets.com/carlito/carlito-700i.woff2

## Connect an agent

Point any MCP client at the BrandSweets fonts endpoint to get this list with scores, or search the catalog:

- Endpoint: https://mcp.brandsweets.com/fonts/mcp
- Tools: `find_alternatives` (e.g. `find_alternatives({ commercialFont: "calibri", limit: 8 })`), `list_commercial_fonts`, `list_fonts`, `suggest_fonts`.