Checkout is the most critical page in any Magento 2 store. A one-second delay at this stage can cost you significantly more than the same delay on a product page — studies consistently show that conversion rates drop 7% for every second of checkout load time. Yet the Magento 2 checkout is notoriously heavy: it loads dozens of JavaScript components, makes multiple AJAX calls, and queries several database tables on every step. This guide walks through the most impactful optimizations you can make to speed up your checkout — from quick wins to deep infrastructure changes. Why Is Magento 2 Checkout So Slow? Before optimizing, it helps to understand the bottlenecks: KnockoutJS + RequireJS overhead — The checkout is built on KnockoutJS with dozens of UI components, each requiring its own module load via RequireJS. Multiple AJAX requests on page load — Shipping methods, totals, customer data, and cart summaries are all fetched asynchronously.…