Euclid
Euclid is a Squarespace theme by Squarespace (Free). Tested on 2026-09-14 with Google Lighthouse via PageSpeed Insights on its own demo store, it scores 59 for mobile speed and 93 for desktop speed, 92/92 for SEO and 94/93 for accessibility (mobile/desktop, 0–100).
Mobile59

Desktop93

Scores
| Mobile | Desktop | |
|---|---|---|
| Speed | 59 | 93 |
| SEO | 92 | 92 |
| Accessibility | 94 | 93 |
| Best practices | 100 | 96 |
Single preset · measured 2 times since 2026-09-14 · Lighthouse via PageSpeed Insights · 0–100, 90+ is good.
Why not 100 — Euclid home page
Mobile
Speed 59 · 41 points to gain
- −25 Largest Contentful Paint medium effort
- −8.9 First Contentful Paint medium effort
- −5.3 Speed Index medium effort
- −1.8 Total Blocking Time medium effort
- 1.9 s Reduce unused JavaScript high effort
- 900 ms Reduce unused CSS high effort
SEO 92 · 8 points to gain
- −7.7 Document does not have a meta description low effort
Accessibility 94 · 6 points to gain
- −4.3 Background and foreground colors do not have a sufficient contrast ratio. medium effort
- −1.9 Heading elements are not in a sequentially-descending order medium effort
Desktop
Speed 93 · 7 points to gain
- −2.8 Speed Index medium effort
- −2.7 Largest Contentful Paint medium effort
- −0.8 Cumulative Layout Shift medium effort
- −0.6 First Contentful Paint medium effort
- 160 ms Reduce unused CSS high effort
SEO 92 · 8 points to gain
- −7.7 Document does not have a meta description low effort
Accessibility 93 · 7 points to gain
- −4.6 Background and foreground colors do not have a sufficient contrast ratio. medium effort
- −2 Heading elements are not in a sequentially-descending order medium effort
Best practices 96 · 4 points to gain
- −3.8 Browser errors were logged to the console medium effort
Presets and pages
| Preset / page | Speed | SEO | A11y | Speed | SEO | A11y | Tested |
|---|---|---|---|---|---|---|---|
| mobile | desktop | ||||||
| Euclid default demo ↗ | 59 | 92 | 94 | 93 | 92 | 93 | 2026-09-14 |
| home ↗ | 59 | 92 | 94 | 93 | 92 | 93 | 2026-09-14 |