At a glance
Desktop-only CWV pass rate, the percentage of real-user desktop page-loads where all three CWVs (LCP, INP, CLS) met Google’s “good” thresholds simultaneously. Pairs with crux_mobile_pass for the device split. Desktop typically runs 5-15 percentage points higher pass rate than mobile because of better network, faster CPUs, and unthrottled rendering. Less critical than mobile for ranking impact (mobile-first indexing weights mobile heavily) but still important for desktop user experience and conversion.
| What it counts | (count of desktop page-loads where LCP < 2,500ms AND INP < 200ms AND CLS < 0.1) ÷ (total desktop page-loads in 28-day window) × 100. Same all-three-pass calculation as mobile but filtered to form_factor: DESKTOP. |
| Sample type | Field data sourced from CrUX. Desktop-only filter applied. |
| Why desktop matters less for ranking but still matters | Ranking: mobile-first indexing means Google primarily ranks on mobile CWV. Desktop CWV plays a smaller role. User experience and conversion: desktop users who reach a slow site bounce just like mobile users; conversion rate impact is similar. Specific cases where desktop matters more: B2B sites with predominantly desktop traffic; high-AOV verticals (luxury, jewellery, electronics) where users spend longer comparison-shopping on desktop. |
| Why desktop runs faster | (1) Unthrottled network (broadband or wifi) vs mobile 4G. (2) Faster CPUs (no mid-tier Android emulation; users have full PC processors). (3) Larger viewports select different LCP elements (hero text often replaces large images as LCP element). (4) Desktop users have fewer connectivity issues (battery, signal, network congestion). |
| Same Google thresholds | LCP good ≤ 2,500ms (same as mobile); INP good ≤ 200ms (same); CLS good ≤ 0.1 (same). The 75 percent pass rate threshold for CWV ranking signal is the same. Google doesn’t apply different thresholds for desktop; the metric definitions are identical, just the measurement comes from desktop sessions. |
| Sample size threshold | CrUX requires sufficient desktop traffic (~1,000+ desktop sessions per 28-day window). Mobile-dominant sites may have null desktop data. |
| Currency | n/a, this is a percentage. |
| Time window | 28D (CrUX-fixed). |
| Alert trigger | < 75 percent (red). Sub-thresholds: amber 75-90 percent, red < 75 percent. |
| Sentiment key | psi_cwv_pass |
| Roles | owner, marketing, operations |
Calculation
Calculated automatically from your Website Performance (PageSpeed + CrUX) data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.Worked example
A UK-based BigCommerce fashion store, desktop field data Wednesday 15 May 26.| Sub-metric | Desktop p75 | Desktop good % | Mobile good % (compare) | Gap |
|---|---|---|---|---|
| LCP | 2,140ms (good) | 88% | 56% | +32 pp |
| INP | 280ms (needs improvement) | 84% | 71% | +13 pp |
| CLS | 0.080 (good) | 91% | 78% | +13 pp |
| All-3 desktop pass rate | 78.4% | 64.8% mobile | +13.6 pp |
- Desktop pass rate at 78.4 percent is in the passing band (above 75 percent threshold). Desktop users experience CWV-passing performance on a majority of page-loads. Desktop is not the priority for optimisation work; mobile is the bottleneck.
- The 13.6 percentage point mobile-vs-desktop gap is typical. All three sub-metrics show desktop performing significantly better. LCP shows the largest gap (88% desktop vs 56% mobile = 32pp) because mobile slow networks dominate LCP timing; desktop unthrottled networks deliver the same content much faster.
- INP gap is moderate (13pp) because INP depends on JS execution speed which scales with CPU. Desktop CPUs run JS several times faster than mid-tier mobile.
- CLS gap is small (13pp) because CLS measures layout shift which is largely viewport-independent. The gap that exists is mostly explained by mobile having more late-loading widgets (popup, chat) that fire on mobile but mount differently on desktop.
- Desktop being healthy is the silver lining, not the primary target. Don’t optimise desktop first; protect it from regression while optimising mobile.
- However, for B2B-heavy sites or high-AOV verticals, desktop pass rate matters more. If the site has 70+ percent desktop traffic share (rare in fashion ecommerce, common in B2B / wholesale / industrial), desktop optimisation moves up the priority list. The same 78.4 percent desktop pass rate looks more concerning when the user base is predominantly desktop.
- Watch for desktop regression as a side effect of mobile optimisation. Some mobile fixes (lazy-loading below-fold images aggressively) can occasionally hurt desktop performance if not configured carefully. Monitor both pass rates post-mobile-optimisation.
- Compare to mobile pass rate. Confirm desktop is passing while mobile fails (typical pattern). If both fail, optimisation work affects both equally.
- Identify desktop-specific issues if pass rate is amber/red. Server-side rendering issues, slow TTFB, render-blocking work affect desktop too.
- For pass rate above 80 percent, desktop is healthy and doesn’t need active work; protect from regression.
| Time horizon | Action |
|---|---|
| First 1 hour | Compare desktop vs mobile; confirm pattern. |
| First 24 hours | If desktop is failing, address server-side issues that affect both devices first. |
| Day 7-28 | Field metrics absorb fix; re-evaluate. |
Sibling cards merchants should reference together
| Card | Why merchants reach for it |
|---|---|
crux_mobile_pass | Mobile pass rate; the priority device for ranking. |
psi_cwv_pass_rate | Origin-level all-3 pass rate. |
crux_lcp_p75 | LCP sub-metric. |
crux_inp_p75 | INP sub-metric. |
crux_cls_p75 | CLS sub-metric. |
crux_pass_rate_trend | Pass rate over time. |
psi_mobile_vs_desktop_score | Lab device comparison. |
Reconciling against the vendor’s own dashboard
Where to look:- Google Search Console → Core Web Vitals → Desktop, desktop CWV view from the same CrUX dataset.
- PageSpeed Insights, toggle to desktop tab for desktop pass percentage.
- CrUX BigQuery, raw desktop-form-factor data.
| Reason | Direction | What to do |
|---|---|---|
| Window timing. Vortex IQ refreshes daily; CrUX has 1-2 day lag. | Vortex IQ lags | Wait for next refresh. |
| URL grouping. GSC groups URLs; Vortex IQ shows origin aggregate. | Different aggregation | Use per-URL view. |
Known limitations / merchant FAQs
My desktop pass rate is 95 percent and mobile is 65 percent. Where should I focus? Mobile, almost always. Mobile-first indexing means Google primarily ranks on mobile CWV; mobile is also typically 60-80 percent of ecommerce traffic. Desktop being healthy is good, it means your fundamentals (server, theme, content) work, but the gap to mobile is what needs attention. Why does desktop pass rate matter at all if mobile is the priority? Three reasons. (1) B2B / wholesale / industrial verticals have predominantly desktop traffic. (2) High-AOV verticals (luxury, jewellery, electronics) have desktop-dominant comparison-shopping behaviour. (3) Desktop CWV failures still affect conversion even if they don’t affect ranking; failed desktop loads bounce just like failed mobile loads. Can desktop pass rate be lower than mobile? Theoretically yes; very rare in practice. Would require desktop-specific issues like heavy desktop-only widgets, broken responsive design that loads more on desktop, or desktop-specific server issues. Almost always desktop > mobile. My desktop pass rate dropped 10 points overnight. What happened? Same kinds of causes as mobile regression: deploy added new render-blocking resources, content upload (heavy images), third-party update changed behaviour, infrastructure change. Desktop drops are usually slower-onset than mobile because desktop is more forgiving. A 10-point overnight drop is significant and likely traces to a specific deploy or config change. Should I aim for 100 percent desktop pass rate? 90+ percent is achievable and reasonable. 100 percent is structurally hard because some users have edge-case slow conditions (corporate VPNs, restricted networks, very old machines). The marginal cost of pushing from 95 to 100 percent rarely justifies the engineering investment. Why might my CrUX desktop data be missing? Insufficient desktop traffic. CrUX requires ~1,000+ desktop sessions per 28-day window. Mobile-dominant sites (typical fashion/beauty ecommerce) may have plenty of mobile data but insufficient desktop sessions for stable p75. Use lab data (psi_cwv_pass_rate on desktop profile) as fallback.
Can Vortex IQ tell me which desktop URLs are failing?
Per-URL desktop data appears in crux_origin_vs_url when CrUX URL-level desktop data is available. For URLs without CrUX coverage, lab measurement via Lighthouse on desktop profile fills the gap.