1
At a glance the headline numbers for Image CDNs impact
Performance impact by image_cdn provider.
7
Providers ranked
After min-sites filter
14,356
Sites in sample
Combined across all items
0.02
Best CLS (p75)
Fastly Image Optimizer
The State of Web Vitals · Q1 2026 · 94,910 sites · phone 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 | 88.4% | 596 | |
| 2 | Akamai Image Manager | 0.03 | 86.7% | 3,876 | |
| 3 | Bunny Image Optimizer | 0.03 | 87.5% | 9,022 | |
| 4 | Imgix | 0.04 | 86.6% | 432 | |
| 5 | Uploadcare | 0.08 | 82.9% | 54 | |
| 6 | Thumbor | 0.11 | 71.2% | 96 | |
| 7 | Cloudinary | 0.16 | 71.4% | 280 |
The State of Web Vitals · Q1 2026 · 94,910 sites · phone 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% 596 0.02
ImageKit 0% 40 0.02
Bunny Image Optimizer 9.5% 9,022 0.03
Akamai Image Manager 4.1% 3,876 0.03
imgix 0.5% 432 0.04
Uploadcare 0.1% 54 0.08
Sirv 0% 30 0.04
Cloudinary 0.3% 280 0.16
Thumbor 0.1% 96 0.11
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. Cloudinary trails 17 points behind, leaving 29% of its sites failing. computed
The State of Web Vitals · Q1 2026 · 94,910 sites · phone 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 9.5%
822.2s
93132ms
880.03
761.8s
601.1s
Akamai Image Manager 4.1%
792.3s
93136ms
870.03
751.8s
561.2s
Fastly Image Optimizer 0.6%
871.8s
91135ms
880.02
871.4s
78758ms
imgix 0.5%
852.1s
88162ms
870.04
841.5s
75790ms
Cloudinary 0.3%
752.5s
75199ms
710.16
731.8s
571.1s
Thumbor 0.1%
832.2s
83156ms
710.11
831.5s
80680ms
Uploadcare 0.1%
882.1s
80191ms
830.08
861.5s
78736ms
ImageKit 0%
643.2s
81144ms
880.02
602.1s
541.4s
Sirv 0%
772.5s
94110ms
830.04
612.4s
371.6s
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.
Bunny Image Optimizer leads on CLS: 88% of its sites pass. Cloudinary trails at 71%. computed
The State of Web Vitals · Q1 2026 · 94,910 sites · phone field datacorewebvitals.io/state-of-cwv
Related signals Search (4) → Font services (4) → Personalization (5) → CDN (15) → Chrome field data from 94,910 sites, representing millions of real page loads · How we measured
Chrome field data from 94,910 sites, representing millions of real page loads. How we measured.