Swiper vs Underscore.js

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

Top sites by authority

Swiper · Underscore.js · 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

Swiper · Underscore.js · share of sites in each country using one or the other

United States 427,105

171,809

India 239,537

75,536

Brazil 225,038

42,848

Germany 188,085

62,310

United Kingdom 161,180

65,350

France 159,069

54,908

Japan 180,131

26,777

Italy 145,736

58,817

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, Sep 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 Swiper sites · All Underscore.js sites