On this page
- The three metrics
- Global pass rates (as-of 2026-05)
- Ecommerce underperformance
- Platform benchmarks (as-of 2025-11)
- Conversion rate impact
- Case studies
- CWV as an SEO ranking signal
- INP: the most complex CWV for ecommerce
- Common failure patterns in ecommerce
- What practitioners say about fixes
- Contradictions
- Key terms
- 2025–2026 updates
- Benchmarks
Core Web Vitals
Core Web Vitals
Google's three field-measured UX metrics — LCP, INP, and CLS — that quantify loading speed, interactivity, and visual stability respectively. Since 2021, CWV have been a confirmed Google ranking signal and are assessed from real Chrome user data (CrUX) at the 75th percentile over a rolling 28-day window. Ecommerce sites structurally underperform the global CWV average due to heavy product imagery, JS-driven filtering, and third-party scripts — making CWV a higher-effort but higher-stakes target for online retailers than for most other site categories.
The three metrics
| Metric | What it measures | Good threshold | Previous metric |
|---|---|---|---|
| LCP — Largest Contentful Paint | Time until the largest above-the-fold element renders | ≤ 2,500 ms | — |
| INP — Interaction to Next Paint | Worst responsiveness delay across all user interactions | ≤ 200 ms | FID (replaced March 12, 2024) |
| CLS — Cumulative Layout Shift | Cumulative unexpected visual shift during page lifetime | ≤ 0.1 | — |
All three thresholds are assessed at the 75th percentile of real Chrome sessions. An origin must pass all three simultaneously to receive an "overall good" CWV assessment. [digitalapplied.com, 2026-06-12]
Important: INP replaced First Input Delay (FID) as a Core Web Vital on 12 March 2024. Pass-rate data citing FID from before that date is not comparable to INP figures — FID measured only the first interaction and was significantly easier to pass. [digitalapplied.com, 2026-06-12]
Global pass rates (as-of 2026-05)
- 55.9% of all tracked origins globally pass all three CWV simultaneously (May 2026 CrUX; 18.4 million origins tracked). [digitalapplied.com, 2026-06-12]
- Individual metric rates (May 2026 CrUX): 68.6% good LCP · 81.3% good CLS · 86.6% good INP — LCP is the hardest metric to pass. [digitalapplied.com, 2026-06-12]
- Mobile origins pass all three at ~48–50% versus ~56–57% for desktop (7–9 pp gap). [digitalapplied.com, 2026-06-12; DebugBear, 2025-12-05]
- On mobile specifically, only ~62% achieve good LCP versus ~77% for INP and ~81% for CLS — loading, not responsiveness or stability, is the dominant mobile failure mode. [digitalapplied.com, 2026-06-12]
Ecommerce underperformance
Ecommerce sites pass all three CWV at approximately 39% — lower than the global average at the same snapshot period (42%). [ighenatt.es, 2026] Three structural reasons are identified across sources:
Product imagery as the dominant LCP element — product images are the LCP element on 78% of category pages and 84% of product pages. [ighenatt.es, 2026] Category pages may display 20–60 product images simultaneously. [ighenatt.es, 2026]
JS-driven filtering → INP overload — stores with category filters built on reactive JS frameworks (React, Vue) without optimisation typically show INP of 300–500 ms against the ≤200 ms threshold; each filter change triggers server queries, DOM recalculations, product listing updates, and URL changes synchronously on the main thread. [ighenatt.es, 2026]
Third-party scripts dominate request volume — 45% of web requests on the open web are third-party; performance.now() 2024 identifies this as the single largest structural source of INP degradation in ecommerce environments. [Jason Grigsby, Web Conferences Amsterdam, 2024-11-14] On Shopify specifically, r/shopify practitioners (2025) report that app scripts are the most common root cause of failing CWV, particularly INP. [r/shopify, 2025-10]
Platform benchmarks (as-of 2025-11)
| Platform | CWV overall pass rate | Notes |
|---|---|---|
| Duda | 84.87% | Highest tracked |
| Shopify | 75.22% | Hosted CDN; 95% good TTFB |
| Wix | 74.86% | Hosted |
| Squarespace | 70.39% | Hosted |
| WordPress | 46.28% | Fails on LCP/loading; INP pass rate 85.89% (comparable to hosted platforms) |
| Magento / Adobe Commerce | ~40–41% | — |
| WooCommerce | ~31% | — |
| PrestaShop | ~28% | — |
[digitalapplied.com, 2026-06-12; Hostingstep, 2025-12-25; ighenatt.es, 2026 (earlier snapshot — see Contradictions)]
Note on WordPress: Its 46.28% overall pass rate is misleading because its INP is 85.89% — the failure is on loading (LCP + TTFB), pointing to hosting and theme configuration as the fix, not JavaScript architecture. Shopify achieves 95% good TTFB versus WordPress at 32%, driven by edge caching on hosted infrastructure. [digitalapplied.com, 2026-06-12; Hostingstep, 2025-12-25]
Conversion rate impact
- Deloitte/Google "Milliseconds Make Millions": every 0.1 seconds of improvement in site load speed increases retail conversion rates by 8% (reported as 8.4% in some secondary citations). [ighenatt.es, 2026; nostra.ai, 2025-06-03; original study paywalled]
- CWV do correlate with conversion rate, "but the relationship is very site-specific." [Tammy Everts, performance.now() 2024, https://www.youtube.com/watch?v=rU3-hOhYW2Y]
[!unverified] A widely repeated claim that "sites passing all three CWV show 24% higher conversion rates" appears across multiple ecommerce SEO publications. No named primary study has been identified. This figure should not be cited without a traceable source.
The ecommerce user journey spans multiple page types and interactions — category browsing, filtering, image zoom, size selection, add-to-cart, checkout, coupon application, payment confirmation — so poor CWV at any step is multiplicative in impact, not additive. [ighenatt.es, 2026]
Case studies
- Rakuten 24: +33% conversions, +53% revenue per visitor after optimising all three CWV. [ighenatt.es, 2026; original: web.dev, date unknown]
- Vodafone Italy: +8% sales after LCP improved by 31%. [ighenatt.es, 2026; original: web.dev, likely 2021–2022]
- Tokopedia (50M+ monthly page views): +35% click-through rate, +8% conversions. [Hostingstep, 2025-12-25; original case study ~2021]
- Agrofy (Latin American marketplace): LCP improved 70% → load abandonment dropped from 3.8% to 0.9% (–76%). [NitroPack, 2026-03-26; original: web.dev, pre-2023]
CWV as an SEO ranking signal
Google confirmed CWV as a ranking signal since 2021. Google's John Mueller has described its weight as: "It is a ranking factor, and it's more than a tie-breaker, but it also doesn't replace relevance." [digitalapplied.com, 2026-06-12]
Key technical note: Google uses CrUX field data, not Lighthouse lab scores, for ranking assessment. The CrUX assessment updates on a 28-day rolling window — improvements can take up to four weeks to influence ranking signals. [digitalapplied.com, 2026-06-12]
INP: the most complex CWV for ecommerce
INP (Interaction to Next Paint) replaced FID in March 2024 and is the most structurally challenging CWV for ecommerce sites because:
- More than 25% of INP events happen after 20 seconds on page — INP is not just a page-load problem; it measures sustained interaction responsiveness throughout a session. [Erwin Hofman & Karlijn Löwik, performance.now() 2024]
- Device memory is a strong predictor — lower memory mobile devices consistently produce worse INP; a 23% performance gap exists between mobile and desktop INP. [Hofman & Löwik, performance.now() 2024]
- LoAF (Long Animation Frames API) is the primary diagnostic tool — it enables identification of which specific scripts are blocking the main thread and for how long. One case: removing a single 3,950 ms script found via LoAF produced a 77% INP improvement. [Hofman & Löwik, performance.now() 2024]
- TBT (Lighthouse's INP proxy) has a weak correlation with real-user INP — teams optimising for Lighthouse TBT scores may be misled about real-world responsiveness. [Hofman & Löwik / RUMvision, 2024]
Annie Sullivan (who led CWV development at Google) recommends teams build custom north-star metrics around their critical user interactions — add to cart, checkout completion — using element timing, event timing, LoAF, and user timing marks, rather than treating CWV scores as the final word. [performance.now() 2024, https://www.youtube.com/watch?v=ORg88SshSEQ]
Common failure patterns in ecommerce
| Pattern | Metric affected | Evidence |
|---|---|---|
| Lazy-loading applied to LCP hero image | LCP | 731,000 sites do this, including 38 in the top 1,000 [Paul Calvano, performance.now() 2024]; r/shopify merchant fixed LCP from 3.5s → 1.2s by disabling it [r/shopify, 2022] |
| Third-party app scripts (Shopify) | INP | Identified as #1 cause by r/shopify practitioners in 2025; injected scripts block main thread |
| Promotional banners without reserved dimensions | CLS | Can generate CLS of 0.15–0.25 on its own [ighenatt.es, 2026] |
| Dynamic page TTFB on self-hosted platforms | LCP | WooCommerce/PrestaShop TTFB 300–600 ms without caching [ighenatt.es, 2026] |
| Fake PageSpeed score gigs | None (misleading) | Fiverr gigs that suppress apps during Lighthouse runs inflate lab scores; Shopify has warned about this [r/shopify, 2025-09] |
What practitioners say about fixes
- Shopify themes: old pre-OS 2.0 themes require a full rebuild (not just a theme update) to achieve meaningful CWV gains; architecture is the bottleneck, not image compression alone. [r/shopify, 2025-10]
- GPU animations + yielding: switching from CPU to GPU animations and adding
scheduler.yield()calls produced a 53% INP improvement on DeOlineDrogist.nl. [Hofman & Löwik, performance.now() 2024] - LoAF-guided script removal: identify and remove or defer blocking scripts found via the Long Animation Frames API before attempting other INP optimisations. [Hofman & Löwik, performance.now() 2024]
- Speculation Rules API: prerendering key next pages means JavaScript is already executed before the user's first interaction, improving INP. Shopify deployed speculation rules platform-wide in June 2025. [Hofman & Löwik; DebugBear, 2025-12-05]
- LCP image preload:
<link rel="preload" as="image">for the hero image in the<head>reduces LCP by 0.3–0.8 seconds on product pages. [ighenatt.es, 2026] - RUM over Lighthouse: "Synthetic testing is for testing, not monitoring" — Real User Monitoring (RUM) is the gold standard for production CWV. [Harry Roberts, performance.now() 2024]
Contradictions
Key terms
| Term | Meaning |
|---|---|
| LCP | Largest Contentful Paint — time until the largest visible element (usually a hero image) renders |
| INP | Interaction to Next Paint — worst-case interaction delay experienced by the 75th percentile of users |
| CLS | Cumulative Layout Shift — total unexpected visual movement during a page's lifetime |
| FID | First Input Delay — INP's predecessor; measured only the first interaction, now retired |
| CrUX | Chrome User Experience Report — Google's anonymised field dataset used for CWV ranking assessment |
| LoAF | Long Animation Frames API — Chrome API for diagnosing which scripts block the main thread |
| TBT | Total Blocking Time — Lighthouse's lab-based proxy for INP; correlates poorly with real-user INP |
| RUM | Real User Monitoring — tools (e.g. SpeedCurve, RUMvision, DebugBear) that capture field CWV data |
| Speculation Rules | Chrome API enabling prerendering of likely next pages; improves INP on prerendered pages |
2025–2026 updates
Thresholds: No threshold changes as of 2026-09-06. LCP ≤2.5s, INP ≤200ms, CLS ≤0.1 remain in force. [web.dev/articles/vitals, updated 2024-10-31; developers.google.com/search/docs/appearance/core-web-vitals, updated 2025-12-10]
February 2025 Chrome measurement changes (no threshold changes; measurement accuracy improvements):
- TTFB now counts from the early hints response rather than the HTML document response — sites using early hints saw improved TTFB readings. [debugbear.com/blog/2025-in-web-performance, 2026-08-23]
- LCP for cross-origin images: Chrome now provides a coarsened render time even without the
Timing-Allow-Originheader (Chrome 133), fixing a long-standing undercount. [web.dev/articles/lcp, updated 2025-09-04; debugbear.com/blog/2025-in-web-performance] - INP: text highlighting at the edge of a window no longer inflates INP when the action triggers scrolling. [debugbear.com/blog/2025-in-web-performance]
- CrUX began publishing LCP subpart breakdowns (TTFB → resource load delay → resource load duration → element render delay) for real users — visible in CrUX Vis and DebugBear, not directly in PageSpeed Insights. [debugbear.com/blog/2025-in-web-performance]
Cross-browser support (as-of 2026-09-06):
- LCP and INP are now "Baseline Newly Available" as of December 12, 2025, following Safari 26.2's implementation of the Largest Contentful Paint API and Event Timing API. [web.dev/blog/lcp-and-inp-are-now-baseline-newly-available]
- Firefox added INP support in version 144 (October 2025). [debugbear.com/blog/2025-in-web-performance]
- CLS (Layout Instability API) remains Chromium-only — not supported in Safari or Firefox. Proposed for Interop 2026 but not confirmed. [debugbear.com/blog/2025-in-web-performance]
Potential future CLS tightening: The Chrome team has signalled that if third-party embed layout shift issues are resolved, a more stringent CLS "Good" threshold (0.05 or 0) may be applied in a future iteration. No timeline confirmed. [web.dev/articles/defining-core-web-vitals-thresholds]
scheduler.yield() cross-browser: Available in both Chrome and Firefox as of August 2025 — the key API for breaking up long INP-blocking tasks without setTimeout hacks. [debugbear.com/blog/2025-in-web-performance]
Soft navigations (SPA ecommerce): Still unresolved. Chrome launched a new origin trial for soft navigation performance measurement (August 2025). No stable API yet — SPAs cannot yet report accurate CWV via CrUX for subsequent page views. [debugbear.com/blog/2025-in-web-performance]
Benchmarks
May 2026 CrUX (as-of 2026-05):
| Metric | Global (all origins) | Mobile | Desktop |
|---|---|---|---|
| All three CWV pass | 55.9% | ~48–50% | ~56–57% |
| Good LCP | 68.6% | ~62% | higher |
| Good INP | 86.6% | — | — |
| Good CLS | 81.3% | — | — |
[digitalapplied.com, 2026-06-12; DebugBear, 2025-12-05]
October 2025 CrUX (as-of 2025-10):
| Device | All three pass | vs Oct 2024 | vs Oct 2023 |
|---|---|---|---|
| Desktop | 57.1% | +1.8 pp | +5.7 pp |
| Mobile | 49.7% | +3.0 pp | +6.3 pp |
[debugbear.com/blog/2025-in-web-performance, 2026-08-23]
July 2025 Web Almanac CrUX (as-of 2025-07):
| Metric | Mobile | Desktop |
|---|---|---|
| All three pass | 48% | 56% |
| Good LCP | 62% | 74% |
| Good INP | 77% | 97% |
| Good CLS | 81% | 72% |
Note: Home pages underperform secondary pages — only 45% (mobile) and 47% (desktop) of home pages pass all three CWV, versus 56%/61% for secondary pages. [almanac.httparchive.org/en/2025/performance]
LCP is consistently the primary bottleneck — the lowest-passing individual metric on both mobile and desktop across all snapshot dates. INP on desktop (97%) is near-universal; mobile INP (77%) remains a gap due to device hardware constraints.