Baseline
ELI5 - The Vibe Check
Baseline is the label that finally answers can I actually use this CSS feature yet, without you tab hopping between five different browser support tables. If a feature is marked Widely available, every major browser has supported it for about 30 months straight. It's basically a green light system so you stop guessing and start shipping.
Real Talk
Baseline is a cross browser initiative, backed by the W3C WebDX Community Group and shown on MDN and caniuse, that indicates whether a web platform feature is safe to use across all major browsers. Features are marked Newly available once supported by the latest versions of Chrome, Edge, Firefox, and Safari, and Widely available after roughly 30 months of that support.
When You'll Hear This
"Check Baseline before you reach for a polyfill, it might already be safe to ship." / "Container queries just hit Baseline Widely available, so we can drop the fallback."
Related Terms
Container Query
Container queries are like media queries, but instead of checking the window size, they check the size of the parent container. Finally.
Feature Detection
Feature Detection checks if a browser supports a feature before trying to use it.
Polyfill
A polyfill is a piece of code that teaches old browsers new tricks. Browser doesn't support Promise? Here's a polyfill that fakes it.
Progressive Enhancement
Progressive enhancement means building a web page that works for everyone at its most basic level, then layering on fancy features for browsers that suppor...