---
title: "Speculation Rules API"
description: "1 posts about Speculation Rules API, summarised, each linking to the original."
---

# Speculation Rules API
> 1 posts about Speculation Rules API, summarised, each linking to the original.

## Articles

### [Improving performance by prefetching product pages from Etsy Search](https://yomu.fyi/post/improving-performance-by-prefetching-product-pages-from-etsy-search.md)
- Company: [Etsy](https://yomu.fyi/company/etsy.md)
- Author: David Weinzimmer
- Published: Oct 29, 2025
- Type: Problem & solution

Etsy’s search and web performance teams tested the Speculation Rules API (SRA) to reduce loading time for product listing pages reached from desktop organic search. They added a speculationrules configuration that prefetches eligible listing HTML after a 200-millisecond hover, using URL and data-attribute selectors with moderate eagerness; unlike link prefetch, SRA uses both memory and HTTP caches. The experiment required attention to a two-page memory limit, five-minute retention, non-cacheable listing HTML, video hover behavior, cookies, new-tab targets, and analytics events triggered during prefetches. Results showed 23.6% faster 75th-percentile TTFB, with improvements of 20.7% in FCP, 21.1% in LCP, 20.4% in DOMContentLoaded, and 10.6% in Page Load, while roughly one in 14 prefetches led to navigation.