langchain.com draws its headings and body text in TWK Lausanne 250. It uses 2 fonts in all. We measured it on October 21, 2026.
The fonts langchain.com draws
| Font | Used for | Share of its custom-font text | Licence | How common |
|---|---|---|---|---|
| TWK Lausanne 250 | Headings, Body text | 84.9% | Not verified as obtainable | – |
| Aeonik Mono | Smaller text | 15.1% | Commercial | 2 of 407 sites (rank =29) |
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?
- TWK Lausanne 250: we could not verify that this typeface can be licensed, so we neither recommend it nor link a source.
- Aeonik Mono 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.
langchain.com among ai sites
langchain.com is one of the 31 ai sites we measured. Across them, Inter is the most used font you can get, on 3 of the 31 (10%). All the fonts ai sites use.
What pairing does langchain.com use?
langchain.com uses one family, TWK Lausanne 250, for both headings and body text. So do 280 of the 407 sites we analyzed (69%). Pairings of two different fonts.
Other ai sites we measured
- anthropic.com Anthropic Sans Text, Anthropic Serif Text
- bolt.new Schibsted Grotesk
- character.ai Open Sans, At Hauss
- cursor.com Cursor Gothic, Berkeley Mono, EB Garamond
- deepmind.google Google Sans Flex
- descript.com Booton
See the fonts on all 407 sites.
FAQ
What font does langchain.com use?
langchain.com draws its headings and body text in TWK Lausanne 250. It uses 2 fonts in all: TWK Lausanne 250, Aeonik Mono. We measured it on October 21, 2026.
Is TWK Lausanne 250 free?
We could not verify that TWK Lausanne 250 can be licensed, so we do not state a licence.
What font pairing does langchain.com use?
One family, TWK Lausanne 250, for both headings and body text.
Can I use the same fonts as langchain.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 langchain.com. Each font's licence is on this page, from its source.
How do you know which font langchain.com uses?
We opened langchain.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.