PERFORMANCE
Removing unnecessary CSS from Magento pages
Extensions often load stylesheets on every page. Audit layout XML and front-end assets to remove render-blocking CSS that isn’t needed.
By VISIBI Performance team·Reviewed by Saeed Ak, Co-founder & CTO·Updated 29 September 2026·7 min read
QUICK ANSWER
Extensions often load stylesheets on every page. Audit layout XML and front-end assets to remove render-blocking CSS that isn’t needed.
FROM OUR ENGINEERING WORKREAL CASE
Several stylesheets were loaded globally but not needed on the homepage. Removing them reduced render-blocking CSS and page weight.
KEY TAKEAWAYS
✓Many extensions add CSS globally even when used on one page type.
✓Render-blocking CSS delays first paint and LCP.
✓Move styles to the layout handles where they are actually used.
AT A GLANCE
Where global CSS is often really needed
Checkout-only stylesCheckout
Product-page widgetsProduct
Account areaAccount
Truly global stylesAll pages
Illustrative — audit your own stylesheets.
How to find it
- Chrome DevTools Coverage tab
- PageSpeed “Reduce unused CSS”
- Review default.xml layout files from extensions
- Compare CSS loaded on homepage vs product vs checkout
How to fix it
Move stylesheet declarations from default.xml to specific handles (catalog_product_view, checkout_index_index), remove unused files and re-test.
Common mistakes to avoid
✕Only testing the homepage
✕Optimising lab scores instead of real-user data
✕Adding third-party scripts without a performance budget
✕Leaving load testing until the week before peak
HOW VISIBI CAN HELP
How we help with performance
01MeasureReal-user Core Web Vitals and load tests on key journeys.
02Fix in codeOur developers fix the root cause, not just the symptom.
03Protect peaksAutoscaling, caching and war-room cover for big days.
04MonitorAlerts on speed and checkout regressions with VISIBI Guard.
Get a free quote →Free · No obligation · Reply within 24 hours
Frequently asked questions
Will removing CSS break the design?
Not if you move it to the right page types and test.
Is this relevant for Hyvä?
Hyvä already purges most unused CSS; Luma stores benefit most.
How much faster will it be?
It varies — measure before and after.
SA
Reviewed by Saeed Ak · Co-founder & CTO25 years engineering high-traffic ecommerce, cloud and security platforms. Written by the VISIBI Performance team.Meet the team →
RELATED SERVICES