FrontendHaltPerformance·Intermediate·Conceptual·1 min read
How does subsetting reduce font size?
Short interview answer
A full font file includes glyphs for many scripts and many characters most sites never use. Subsetting strips it to the character ranges actually needed — often just Latin — which can cut the file substantially. unicode-range on @font-face lets the browser only download subsets a page uses.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.