• A web API that enables browsers to prefetch or prerender pages before users navigate to them, resulting in faster or near-instant page loads for multi-page applications. The API uses JSON-defined rules (specified via inline <script type="speculationrules"> elements or HTTP headers) to declare which URLs should be speculatively loaded, with configurable “eagerness” settings that control when speculation occurs based on user interactions like hovering or clicking. The Speculation Rules API was introduced by Google and became available in Chromium-based browsers starting in 2023, superseding the deprecated Chrome-only <link rel="prerender"> feature.

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