Async/Defer Script Advisor

Guide for script loading with async vs defer vs module, including a decision tree, impact analysis, and code generation

Loading Strategy Comparison

Strategy Blocks Parsing Execution Order DOM Ready Best For
(none) Yes In order Before Critical render-blocking scripts
async No Any order Maybe Independent scripts (analytics)
defer No In order Before DOMContentLoaded Scripts needing DOM + order
type="module" No (deferred) In order Before DOMContentLoaded ES modules

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