Boost
Boost is a Shopify theme by Clean Canvas ($380). Tested on 2026-11-08 with Google Lighthouse via PageSpeed Insights on its own demo store, it scores 70 for mobile speed and 81 for desktop speed, 84/84 for SEO and 88/88 for accessibility (mobile/desktop, 0–100). Those are medians across its 4 tested presets; mobile speed across every tested page ranges from 50 to 91. On its marketplace it is rated 4.5 out of 5 from 82 reviews.
Mobile84

Desktop93

Scores
| Mobile | Desktop | |
|---|---|---|
| Speed | 70 | 81 |
| SEO | 84 | 84 |
| Accessibility | 88 | 88 |
| Best practices | 96 | 96 |
Median of 4 presets · measured 120 times since 2026-11-06 · Lighthouse via PageSpeed Insights · 0–100, 90+ is good.
Why not 100 — Blossom home page
Mobile
Speed 84 · 16 points to gain
- −13.3 Largest Contentful Paint medium effort
- −1.5 Cumulative Layout Shift medium effort
- −1.2 Speed Index medium effort
- 450 ms Reduce unused JavaScript high effort
- 240 ms Reduce unused CSS high effort
SEO 92 · 8 points to gain
- −7.7 Links do not have descriptive text low effort
Accessibility 88 · 12 points to gain
- −2.9 Elements with `role="dialog"` or `role="alertdialog"` do not have accessible names. medium effort
- −2.9 ARIA input fields do not have accessible names medium effort
- −2.9 Background and foreground colors do not have a sufficient contrast ratio. medium effort
- −2.9 Links do not have a discernible name medium effort
Best practices 96 · 4 points to gain
- −3.8 Browser errors were logged to the console medium effort
Desktop
Speed 93 · 7 points to gain
- −6.7 Speed Index medium effort
- −0.8 Largest Contentful Paint medium effort
SEO 92 · 8 points to gain
- −7.7 Links do not have descriptive text low effort
Accessibility 88 · 12 points to gain
- −2.9 Elements with `role="dialog"` or `role="alertdialog"` do not have accessible names. medium effort
- −2.9 ARIA input fields do not have accessible names medium effort
- −2.9 Background and foreground colors do not have a sufficient contrast ratio. medium effort
- −2.9 Links do not have a discernible name 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 | ||||||
| Inspire demo ↗ | 76 | 82 | 89 | 78 | 82 | 89 | 2026-11-07 |
| category ↗ | 74 | 100 | 90 | 92 | 100 | 89 | 2026-11-07 |
| home ↗ | 91 | 54 | 91 | 99 | 54 | 91 | 2026-11-07 |
| product ↗ | 63 | 92 | 86 | 44 | 92 | 86 | 2026-11-07 |
| Blossom default demo ↗ | 71 | 95 | 88 | 80 | 95 | 88 | 2026-11-06 |
| category ↗ | 77 | 100 | 90 | 93 | 100 | 89 | 2026-11-08 |
| home ↗ | 84 | 92 | 88 | 93 | 92 | 88 | 2026-11-06 |
| product ↗ | 51 | 92 | 86 | 55 | 92 | 86 | 2026-11-08 |
| Flourish demo ↗ | 69 | 84 | 88 | 83 | 84 | 88 | 2026-11-07 |
| category ↗ | 81 | 100 | 90 | 99 | 100 | 89 | 2026-11-07 |
| home ↗ | 76 | 61 | 88 | 94 | 61 | 88 | 2026-11-07 |
| product ↗ | 50 | 92 | 86 | 55 | 92 | 86 | 2026-11-07 |
| Boost demo ↗ | 65 | 84 | 88 | 81 | 84 | 88 | 2026-11-07 |
| category ↗ | 70 | 100 | 90 | 91 | 100 | 89 | 2026-11-07 |
| home ↗ | 74 | 61 | 88 | 97 | 61 | 88 | 2026-11-07 |
| product ↗ | 51 | 92 | 86 | 55 | 92 | 86 | 2026-11-07 |