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 · 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 | 88.5% | 596 | |
| 2 | Imgix | 0.04 | 87.0% | 432 | |
| 3 | Bunny Image Optimizer | 0.04 | 86.3% | 9,022 | |
| 4 | Akamai Image Manager | 0.05 | 85.4% | 3,876 | |
| 5 | Uploadcare | 0.07 | 82.7% | 54 | |
| 6 | Cloudinary | 0.13 | 73.0% | 280 | |
| 7 | Thumbor | 0.19 | 60.9% | 96 |
The State of Web Vitals · Q1 2026 · 94,910 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% 596 0.02
imgix 0.5% 432 0.04
Bunny Image Optimizer 9.5% 9,022 0.04
Akamai Image Manager 4.1% 3,876 0.05
Uploadcare 0.1% 54 0.07
Sirv 0% 30 0.09
ImageKit 0% 40 0.08
Cloudinary 0.3% 280 0.13
Thumbor 0.1% 96 0.19
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
89% of Fastly Image Optimizer sites pass CLS. Cloudinary trails 16 points behind, leaving 27% of its sites failing. computed
The State of Web Vitals · Q1 2026 · 94,910 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 9.5%
832.2s
96113ms
860.04
771.7s
601.2s
Akamai Image Manager 4.1%
812.2s
96116ms
850.05
771.7s
571.2s
Fastly Image Optimizer 0.6%
891.6s
94117ms
890.02
901.2s
81721ms
imgix 0.5%
862.0s
92137ms
870.04
851.5s
74825ms
Cloudinary 0.3%
792.4s
79175ms
730.13
751.8s
611.1s
Thumbor 0.1%
842.0s
92135ms
610.19
871.5s
76755ms
Uploadcare 0.1%
882.0s
85168ms
830.07
891.5s
80718ms
ImageKit 0%
633.2s
88144ms
780.08
632.1s
491.3s
Sirv 0%
752.5s
96102ms
790.09
622.4s
401.7s
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: 89% of its sites pass. Cloudinary trails at 73%. computed
The State of Web Vitals · Q1 2026 · 94,910 sites · all devices 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.