readwise.io draws its headings and body text in Source Serif 4. It uses 3 fonts in all. We measured it on November 4, 2026.
The fonts readwise.io draws
| Font | Used for | Share of its custom-font text | Licence | How common |
|---|---|---|---|---|
| Source Serif 4 | Headings, Body text | 39.1% | Open source | 3 of 845 sites (rank =41) |
| Inter | Smaller text | 30.6% | Open source | 126 of 845 sites (rank 1) |
| Albert Sans | Smaller text | 29% | Open source | – |
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?
- Source Serif 4 is open source and free to use, including commercially. Get it from Google Fonts.
- Inter is open source and free to use, including commercially. Get it from Google Fonts.
- Albert Sans is open source and free to use, including commercially. Get it from Google Fonts.
readwise.io among saas and productivity sites
readwise.io is one of the 75 saas and productivity sites we measured. Across them, Inter is the most used font you can get, on 23 of the 75 (31%). All the fonts saas and productivity sites use.
What pairing does readwise.io use?
readwise.io uses one family, Source Serif 4, for both headings and body text. So do 567 of the 845 sites we analyzed (67%). Pairings of two different fonts.
Other saas and productivity sites we measured
- ahrefs.com Inter, Ahrefs
- bamboohr.com Inter, Fields
- bitwarden.com Inter
- box.com Inter
- brevo.com Inter, Tomato Grotesk
- cal.com Cal Sans, Matter, Inter
See the fonts on all 845 sites.
FAQ
What font does readwise.io use?
readwise.io draws its headings and body text in Source Serif 4. It uses 3 fonts in all: Source Serif 4, Inter, Albert Sans. We measured it on November 4, 2026.
Is Source Serif 4 free?
Yes. Source Serif 4 is open source and free for commercial use, according to Google Fonts.
What font pairing does readwise.io use?
One family, Source Serif 4, for both headings and body text.
Can I use the same fonts as readwise.io 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 readwise.io. Each font's licence is on this page, from its source.
How do you know which font readwise.io uses?
We opened readwise.io 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.