ai21.com draws its headings in Aeonik and its body text in Söhne. It uses 3 fonts in all. We measured it on November 4, 2026.
The fonts ai21.com draws
| Font | Used for | Share of its custom-font text | Licence | How common |
|---|---|---|---|---|
| Aeonik | Headings | 43.7% | Commercial | 11 of 845 sites (rank =11) |
| Söhne | Body text | 43.1% | Commercial | 10 of 845 sites (rank 14) |
| Inter | Smaller text | 13.1% | Open source | 126 of 845 sites (rank 1) |
Share is how much of the page’s custom-font text each font draws. System fonts and icon fonts are never counted. Each site was opened twice in a real browser and Chrome was asked which font file drew each piece of text. We count a font for a site only if both runs saw it and it drew at least 2% of the site’s custom-font text. The full method.
Can I use the same fonts?
- Aeonik is sold under a commercial licence by CoType Foundry. Licence it from CoType Foundry; copying the file from a site that uses it is not a licence.
- Söhne is sold under a commercial licence by Klim Type Foundry. Licence it from Klim Type Foundry; copying the file from a site that uses it is not a licence.
- Inter is open source and free to use, including commercially. Get it from Google Fonts.
Free fonts in a similar style
If you cannot license Aeonik, these free fonts are in the same style (sans serif) and real sites use them: Inter (126 sites), Roboto (43 sites), Open Sans (26 sites), Geist (18 sites). If you cannot license Söhne, these free fonts are in the same style (sans serif) and real sites use them: Inter (126 sites), Roboto (43 sites), Open Sans (26 sites), Geist (18 sites). A similar style is not the same typeface, so compare them side by side before you commit.
ai21.com among ai sites
ai21.com is one of the 62 ai sites we measured. Across them, Inter is the most used font you can get, on 10 of the 62 (16%). All the fonts ai sites use.
What pairing does ai21.com use?
Aeonik for headings with Söhne for body text does not repeat on another analyzed site, so there is no shared pairing to show. Pairings that do repeat.
Other ai sites we measured
- copy.ai Inter, ABC
- elevenlabs.io Inter, Geist Mono, KMR Waldenburg Buch
- kaiber.ai Inter
- lexica.art Inter
- mistral.ai ALT Mistral, Inter
- murf.ai Inter, Roboto Flex
See the fonts on all 845 sites.
FAQ
What font does ai21.com use?
ai21.com draws its headings in Aeonik and its body text in Söhne. It uses 3 fonts in all: Aeonik, Söhne, Inter. We measured it on November 4, 2026.
Is Aeonik free?
No. Aeonik is sold under a commercial licence by CoType Foundry.
What font pairing does ai21.com use?
Aeonik for headings and Söhne for body text. It does not repeat on another analyzed site.
Can I use the same fonts as ai21.com on my own site?
Only if the licence allows it. Free and open-source fonts can be used freely. Commercial fonts need your own licence, even though you can see the file on ai21.com. Each font's licence is on this page, from its source.
How do you know which font ai21.com uses?
We opened ai21.com in a real browser and asked Chrome which font file drew each piece of text, twice in separate sessions. A font counts only if both runs saw it and it drew at least 2% of the site's custom-font text.
Can I check a different website?
Yes. Paste its address into the free font finder.