Source Serif 4 and Source Sans 3 Font Pairing

Source Serif 4 and Source Sans 3 are a matched pairing from Adobe’s open source type family. The serif sets the headings at weight 600, and the sans carries the body. Because the two were drawn to work together, the page feels unified from top to bottom, which suits reports, documentation, resumes and long reads.

Why Source Serif 4 and Source Sans 3 Work Together

Source Sans 3, designed by Paul D. Hunt, was Adobe’s first open source type family and was intended to work well in user interfaces. Source Serif 4 was designed to complement it, with a careful match of letter proportions and typographic colour. It is a transitional serif loosely based on the work of Pierre Simon Fournier, and it keeps some of his quirks, such as the bottom serif on the b.

This is a pairing with almost no risk. The two fonts share proportions, so a heading and a paragraph sit together naturally even though one has serifs and the other does not. You get the clear separation of a serif and a sans along with the consistency of a single family. It looks calm, professional and quietly well made.

Where Source Serif 4 and Source Sans 3 Work Best

Reports and documentation suit this pair best, since they mix long text with headings, tables and notes. A research group or nonprofit can publish papers that look credible on screen. It also works well on resumes, where the serif names and job titles give a traditional feel while the sans keeps the details compact. Technical blogs benefit from the same clean rhythm.

Weights and Sizes to Use

Set Source Serif 4 at 600 for headings, with 700 for a firmer title; the family runs from 200 to 900 with italics and includes optical sizes. Use Source Sans 3 at 400 for body text and 600 for bold. Body text works well at 17 to 18px with a line height near 1.6, and headings should sit around 1.2.

Things to Watch

A matched pair can look a little too polite, so it needs clear differences in size to give the page some hierarchy. If a heading sits only slightly larger than the body, the page will look flat. Make sure you load Source Sans 3 and Source Serif 4, the current versions, since older tutorials mention Source Sans Pro and Source Serif Pro.