Copperlane Astro + EmDash CMs
Copperlane Astro + EmDash CMs is a Astro theme by Lexington Themes (Paid). Tested on 2026-09-26 with Google Lighthouse via PageSpeed Insights on its own demo store, it scores 77 for mobile speed and 98 for desktop speed, 66/66 for SEO and 100/100 for accessibility (mobile/desktop, 0–100). Note: its demo home page is heavy — 11 MB — heavier than a typical store, so the speed score may understate the theme.
Mobile77

Desktop98

Scores
| Mobile | Desktop | |
|---|---|---|
| Speed | 77 | 98 |
| SEO | 66 | 66 |
| Accessibility | 100 | 100 |
| Best practices | 100 | 100 |
Single preset · measured 2 times since 2026-09-26 · Lighthouse via PageSpeed Insights · 0–100, 90+ is good.
Why not 100 — Copperlane Astro + EmDash CMs home page
Mobile
Speed 77 · 23 points to gain
- −21.8 Largest Contentful Paint medium effort
- −1.3 First Contentful Paint medium effort
- 150 ms Reduce unused JavaScript high effort
SEO 66 · 34 points to gain
- −33.6 Page is blocked from indexing low effort
Desktop
Speed 98 · 2 points to gain
- −2 Largest Contentful Paint medium effort
SEO 66 · 34 points to gain
- −33.6 Page is blocked from indexing low effort
Presets and pages
| Preset / page | Speed | SEO | A11y | Speed | SEO | A11y | Tested |
|---|---|---|---|---|---|---|---|
| mobile | desktop | ||||||
| Copperlane Astro + EmDash CMs default demo ↗ | 77 | 66 | 100 | 98 | 66 | 100 | 2026-09-26 |
| home ↗ | 77 | 66 | 100 | 98 | 66 | 100 | 2026-09-26 |