The State of Web Vitals

Image CDNs impact

Performance impact by image_cdn provider.

Field data PhoneDesktopAll Scope All sites Q2 2026 edition · All devices field outcomes
Metric LCP INP CLS
1

At a glance the headline numbers for Image CDNs impact

Performance impact by image_cdn provider.

9
Providers ranked
After min-sites filter
27,247
Sites in sample
Combined across all items
0.02
Best CLS (p75)
Fastly Image Optimizer
The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
2

The ranking sorted by CLS at p75, fastest first

# Provider CLS p75 Passing Sites
1 Fastly Image Optimizer 0.02 87.5%
1,139
2 ImageKit 0.05 79.7%
78
3 Imgix 0.05 86.6%
805
4 Akamai Image Manager 0.05 85.0%
7,230
5 Bunny Image Optimizer 0.05 86.1%
17,146
6 Uploadcare 0.06 86.2%
92
7 Sirv 0.08 80.0%
57
8 Cloudinary 0.14 71.2%
512
9 Thumbor 0.21 60.1%
188
The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
3

Passing CLS per provider which group passes the CLS most often

ProviderSitesPassing CLSp75
Fastly Image Optimizer 0.6% 1,139 88% 0.02
imgix 0.4% 805 87% 0.05
Uploadcare 0% 92 86% 0.06
Bunny Image Optimizer 9% 17,146 86% 0.05
Akamai Image Manager 3.8% 7,230 85% 0.05
Sirv 0% 57 80% 0.08
ImageKit 0% 78 80% 0.05
Cloudinary 0.3% 512 71% 0.14
Thumbor 0.1% 188 60% 0.21
Good Needs Improvement Poor Sorted best-passing first · median colored by its own rating · pass = good CLS (0.1 at p75) · one value per site

88% of Fastly Image Optimizer sites pass CLS. Thumbor trails 28 points behind, leaving 40% of its sites failing. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
4

All five vitals at once the whole category without toggling - cell is the pass rate, small number the p75

LCP
INP
CLS
FCP
TTFB
Bunny Image Optimizer 9%
822.2s
96113ms
860.05
771.7s
591.2s
Akamai Image Manager 3.8%
812.2s
96116ms
850.05
771.7s
571.2s
Fastly Image Optimizer 0.6%
881.7s
93118ms
880.02
911.2s
81720ms
imgix 0.4%
872.0s
91136ms
870.05
851.5s
75819ms
Cloudinary 0.3%
792.4s
76182ms
710.14
761.8s
591.1s
Thumbor 0.1%
842.2s
95133ms
600.21
841.6s
65963ms
Uploadcare 0%
882.0s
88154ms
860.06
871.4s
82704ms
ImageKit 0%
663.1s
84147ms
800.05
682.0s
501.2s
Sirv 0%
762.5s
96111ms
800.08
662.2s
431.5s
60%95%+ passing Cell: pass rate, small number = p75 · faded rows: under 100 sites

One row per provider, one column per vital - the cell is the share of sites passing, the small number the p75. No toggling needed to see where the category actually differs.

Fastly Image Optimizer leads on CLS: 88% of its sites pass. Thumbor trails at 60%. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
Related signals Search (5) → Font services (4) → Personalization (5) → CDN (15) → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured