Guest Checkout Performance Issue

[sridharkat57db]

Hi

We are seeing performance issues on check out page, page load time is ~12 secs and Dom Load time is ~3 secs, we observed the following issues.

1. Checkout URL is taking ~ 2.5 secs

2. Loading many JS & CSS

and the pattern is inconsistent, DOM load, page loads takes sometimes ~15 secs.

please suggest

1. initial request (checkout/?persistent_remember_me=on#shipping) is taking ~ 2 secs, How to reduce the load time?

2. What external modules needs to be disabled to improve the performance? Guest Checkout page is calling Facebook events, zendesk, and several other external modules.

3. How to improve the guest checkout page performance?

[rimshadevr27ac]

1. Reduce Initial Load Time

• Optimize server resources (e.g., use PHP 8.2+).
• Implement full-page caching for static parts.
• Optimize database queries and use indexes.
• Enable HTTP/2, Gzip/Brotli compression, and a CDN for assets.

2. Disable Unnecessary Modules

• Audit external scripts (e.g., Facebook Events, Zendesk).
• Disable non-critical scripts on the checkout page.
• Defer or async third-party scripts and manage them via Google Tag Manager.

3. Optimize Front-End Performance

• Minify/combine CSS & JS (e.g., Autoptimize).
• Defer non-critical JS, lazy-load images, and reduce API calls.
• Use modern formats (e.g., WebP, WOFF2) and enable browser caching.

Tools to Use

• Monitor performance with Lighthouse or GTmetrix.
• For Magento: Enable Varnish cache and optimize indexers.
• For WordPress: Disable unnecessary plugins and use lightweight checkout plugins.

This should reduce page load times and enhance the user experience.