Bootstrap vs UIKit

Head-to-head usage across the sites we track.

Top sites by authority

Bootstrap · UIKit · how many of each technology's sites sit in the web's highest authority tiers

Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.

By country

Bootstrap · UIKit · share of sites in each country using one or the other

United States 886,770

39,677

India 429,293

12,588

Germany 322,762

19,335

United Kingdom 295,976

9,971

France 279,130

9,948

Brazil 273,285

9,903

Italy 251,088

11,885

Spain 202,979

9,100

Audience countries from the Chrome UX Report, top markets of either technology.

Real user performance

Median site's p75 values from the Chrome UX Report, Jun 2026. Lower is better; green meets Google's "good" threshold. This describes the sites that use each technology, not the technology's own overhead.

Sites that switched

Domains that dropped one technology and adopted the other within about a year, data nobody else gives away free.

All Bootstrap sites · All UIKit sites