1
At a glance the headline numbers for Image CDNs impact
Performance impact by image_cdn provider.
9
Providers ranked
After min-sites filter
27,273
Sites in sample
Combined across all items
0.02
Best CLS (p75)
ImageKit
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
2
The ranking sorted by CLS at p75, fastest first
| # | Provider | CLS p75 | Passing | Sites | |
|---|---|---|---|---|---|
| 1 | ImageKit | 0.02 | 88.5% | 79 | |
| 2 | Fastly Image Optimizer | 0.02 | 86.7% | 1,142 | |
| 3 | Sirv | 0.03 | 86.7% | 57 | |
| 4 | Akamai Image Manager | 0.03 | 86.4% | 7,236 | |
| 5 | Bunny Image Optimizer | 0.03 | 87.8% | 17,162 | |
| 6 | Imgix | 0.05 | 86.1% | 805 | |
| 7 | Uploadcare | 0.08 | 82.1% | 92 | |
| 8 | Thumbor | 0.11 | 71.7% | 188 | |
| 9 | Cloudinary | 0.17 | 68.7% | 512 |
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
3
Passing CLS per provider which group passes the CLS most often
ProviderSitesPassing CLSp75
ImageKit 0% 79 0.02
Bunny Image Optimizer 9% 17,162 0.03
Fastly Image Optimizer 0.6% 1,142 0.02
Sirv 0% 57 0.03
Akamai Image Manager 3.8% 7,236 0.03
imgix 0.4% 805 0.05
Uploadcare 0% 92 0.08
Thumbor 0.1% 188 0.11
Cloudinary 0.3% 512 0.17
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 Bunny Image Optimizer sites pass CLS. Cloudinary trails 19 points behind, leaving 31% of its sites failing. computed
The State of Web Vitals · Q2 2026 · 189,915 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
ImageKit 0%
672.7s
80170ms
880.02
642.0s
541.3s
Sirv 0%
802.4s
95124ms
870.03
602.2s
461.4s
Akamai Image Manager 3.8%
792.3s
92136ms
860.03
741.8s
551.2s
Bunny Image Optimizer 9%
812.2s
93133ms
880.03
751.8s
591.2s
imgix 0.4%
852.1s
87156ms
860.05
841.5s
75807ms
Thumbor 0.1%
832.3s
88151ms
720.11
781.8s
70909ms
Fastly Image Optimizer 0.6%
861.8s
91137ms
870.02
881.4s
77772ms
Uploadcare 0%
882.2s
86175ms
820.08
831.5s
80719ms
Cloudinary 0.3%
752.5s
70220ms
690.17
731.9s
551.1s
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 69%. computed
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
Related signals Search (6) → Font services (4) → Personalization (6) → CDN (16) → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured
Chrome field data from 189,915 sites, representing millions of real page loads. How we measured.