Karim Salman
At Kraken.io we are pretty good at image optimization. This time we checked how well Alexa’s Top 100 Global Sites are optimized. On the 3rd of July 2014 we crawled those 100 websites and optimized all of their images – not only those found in img src but also those from CSS files (background images).
On average we were able to save 12% and 33% (lossless and lossy) with proper image optimization on Alexa’s top 100 ranked sites.
Surprisingly there are only five websites in the top 100 which send WebP images to compatible browsers: Youtube.com, Yandex.ru, Ebay.com, Fifa.com and Odnoklassniki.ru.
The following table shows optimization results for each crawled website. You can download the detailed report for each website in the CSV format here.
| Website | Images | Original | Lossless (% Savings) | Lossy (% Savings) |
| TOTAL | 5069 | 80.37 MB | 70.51 MB (12.26%) | 53.81 MB (33.04%) |
| 1. google.com | 6 | 297.91 KB | 196.34 KB (34.09%) | 126.89 KB (57.41%) |
| 2. facebook.com | 81 | 554.12 KB | 520.58 KB (6.05%) | 476.26 KB (14.05%) |
| 3. youtube.com | 44 | 308.84 KB | 212.57 KB (31.17%) | 207.33 KB (32.87%) |
| 4. yahoo.com | 52 | 937.89 KB | 892.52 KB (4.84%) | 736.64 KB (21.46%) |
| 5. baidu.com | 3 | 10.34 KB | 7.12 KB (31.16%) | 3.96 KB (61.69%) |
| 6. wikipedia.org | 15 | 155.91 KB | 150.21 KB (3.66%) | 71.86 KB (53.91%) |
| 7. qq.com | 136 | 1.29 MB | 1.13 MB (12.73%) | 705.63 KB (46.64%) |
| 8. twitter.com | 18 | 376.75 KB | 268.43 KB (28.75%) | 142.19 KB (62.26%) |
| 9. taobao.com | 81 | 2.51 MB | 2.32 MB (7.39%) | 1.35 MB (46.01%) |
| 10. amazon.com | 116 | 2.65 MB | 2.54 MB (4.25%) | 1.61 MB (39.51%) |
| 11. live.com | 5 | 495.39 KB | 354.51 KB (28.44%) | 101.65 KB (79.48%) |
| 12. linkedin.com | 65 | 205.74 KB | 177.78 KB (13.59%) | 159.17 KB (22.64%) |
| 13. google.co.in | — | — | — | — |
| 14. sina.com.cn | 82 | 1.65 MB | 1.57 MB (4.87%) | 1.05 MB (36.48%) |
| 15. hao123.com | 42 | 531.10 KB | 438.68 KB (17.40%) | 307.30 KB (42.14%) |
| 16. weibo.com | 49 | 605.09 KB | 507.63 KB (16.11%) | 486.12 KB (19.66%) |
| 17. blogspot.com | — | — | — | — |
| 18. tmall.com | 125 | 1.76 MB | 1.68 MB (4.91%) | 1.18 MB (32.91%) |
| 19. sohu.com | 100 | 755.55 KB | 630.56 KB (16.54%) | 432.14 KB (42.80%) |
| 20. yahoo.co.jp | 9 | 35.62 KB | 33.29 KB (6.54%) | 29.59 KB (16.94%) |
| 21. yandex.ru | 6 | 28.16 KB | 26.86 KB (4.61%) | 9.65 KB (65.72%) |
| 22. vk.com | 6 | 203.07 KB | 200.49 KB (1.27%) | 194.33 KB (4.30%) |
| 23. bing.com | — | — | — | — |
| 24. wordpress.com | 2 | 186.93 KB | 186.93 KB (0.00%) | 186.93 KB (0.00%) |
| 25. google.de | — | — | — | — |
| 26. pinterest.com | 4 | 485.94 KB | 458.25 KB (5.70%) | 257.25 KB (47.06%) |
| 27. ebay.com | 147 | 1.12 MB | 1016.36 KB (11.58%) | 659.90 KB (42.59%) |
| 28. 360.cn | 20 | 609.84 KB | 584.71 KB (4.12%) | 307.57 KB (49.57%) |
| 29. google.co.uk | — | — | — | — |
| 30. google.co.jp | — | — | — | — |
| 31. instagram.com | 10 | 178.91 KB | 178.88 KB (0.02%) | 178.88 KB (0.02%) |
| 32. google.fr | — | — | — | — |
| 33. soso.com | 4 | 13.35 KB | 9.14 KB (31.51%) | 6.68 KB (49.93%) |
| 34. 163.com | 187 | 1.86 MB | 1.75 MB (6.05%) | 1.35 MB (27.59%) |
| 35. msn.com | 110 | 351.80 KB | 305.16 KB (13.26%) | 288.00 KB (18.14%) |
| 36. ask.com | 2 | 9.62 KB | 5.88 KB (38.88%) | 4.31 KB (55.24%) |
| 37. tumblr.com | 7 | 1.10 MB | 1023.22 KB (9.08%) | 873.15 KB (22.42%) |
| 38. google.com.br | — | — | — | — |
| 39. mail.ru | 31 | 143.38 KB | 137.38 KB (4.19%) | 98.53 KB (31.28%) |
| 40. microsoft.com | 32 | 380.96 KB | 342.62 KB (10.06%) | 268.01 KB (29.65%) |
| 41. paypal.com | 11 | 1.03 MB | 1.00 MB (2.85%) | 701.85 KB (33.45%) |
| 42. google.ru | — | — | — | — |
| 43. xvideos.com | 139 | 1000.66 KB | 976.46 KB (2.42%) | 908.62 KB (9.20%) |
| 44. google.it | — | — | — | — |
| 45. apple.com | 26 | 4.36 MB | 4.14 MB (5.10%) | 2.90 MB (33.53%) |
| 46. google.es | — | — | — | — |
| 47. imgur.com | 124 | 2.08 MB | 1.94 MB (6.97%) | 1.44 MB (30.94%) |
| 48. imdb.com | 75 | 918.66 KB | 847.84 KB (7.71%) | 770.87 KB (16.09%) |
| 49. craigslist.org | — | — | — | — |
| 50. neobux.com | 7 | 68.43 KB | 62.15 KB (9.18%) | 54.53 KB (20.32%) |
| 51. stackoverflow.com | 7 | 188.08 KB | 156.66 KB (16.71%) | 160.67 KB (14.58%) |
| 52. adcash.com | 10 | 335.08 KB | 242.49 KB (27.63%) | 150.25 KB (55.16%) |
| 53. amazon.co.jp | 79 | 2.08 MB | 2.04 MB (1.97%) | 1.41 MB (32.22%) |
| 54. reddit.com | 26 | 94.67 KB | 86.41 KB (8.73%) | 60.77 KB (35.81%) |
| 55. t.co | — | — | — | — |
| 56. google.com.mx | — | — | — | — |
| 57. xhamster.com | 118 | 3.42 MB | 3.22 MB (5.73%) | 2.88 MB (15.65%) |
| 58. people.com.cn | 97 | 865.03 KB | 743.51 KB (14.05%) | 579.20 KB (33.04%) |
| 59. go.com | 24 | 641.50 KB | 541.60 KB (15.57%) | 283.13 KB (55.86%) |
| 60. google.ca | — | — | — | — |
| 61. fc2.com | 8 | 318.42 KB | 282.89 KB (11.16%) | 151.66 KB (52.37%) |
| 62. adobe.com | 9 | 520.42 KB | 520.29 KB (0.03%) | 367.81 KB (29.32%) |
| 63. bbc.co.uk | 38 | 458.23 KB | 326.65 KB (28.71%) | 320.43 KB (30.07%) |
| 64. xinhuanet.com | 190 | 2.90 MB | 2.36 MB (18.70%) | 1.74 MB (40.11%) |
| 65. cnn.com | 78 | 705.97 KB | 507.46 KB (28.12%) | 383.51 KB (45.68%) |
| 66. aliexpress.com | 128 | 2.08 MB | 1.81 MB (12.94%) | 1.22 MB (41.32%) |
| 67. blogger.com | 13 | 259.51 KB | 207.28 KB (20.13%) | 154.98 KB (40.28%) |
| 68. ifeng.com | 70 | 490.24 KB | 442.67 KB (9.70%) | 386.84 KB (21.09%) |
| 69. google.co.id | — | — | — | — |
| 70. wordpress.org | 11 | 429.68 KB | 386.97 KB (9.94%) | 135.44 KB (68.48%) |
| 71. godaddy.com | 15 | 488.21 KB | 483.84 KB (0.89%) | 284.82 KB (41.66%) |
| 72. googleusercontent.com | — | — | — | — |
| 73. alibaba.com | 34 | 237.73 KB | 216.63 KB (8.88%) | 158.45 KB (33.35%) |
| 74. google.com.tr | — | — | — | — |
| 75. vube.com | 81 | 2.64 MB | 2.52 MB (4.75%) | 2.02 MB (23.67%) |
| 76. huffingtonpost.com | 127 | 2.61 MB | 1.78 MB (31.80%) | 1.48 MB (43.53%) |
| 77. fifa.com | 143 | 1.96 MB | 1.72 MB (12.25%) | 1.33 MB (32.01%) |
| 78. espn.go.com | 78 | 594.63 KB | 499.79 KB (15.95%) | 371.29 KB (37.56%) |
| 79. odnoklassniki.ru | 6 | 133.10 KB | 126.45 KB (5.00%) | 123.94 KB (6.88%) |
| 80. pornhub.com | 46 | 447.80 KB | 425.75 KB (4.92%) | 320.63 KB (28.40%) |
| 81. amazon.de | 57 | 562.40 KB | 505.50 KB (10.12%) | 393.02 KB (30.12%) |
| 82. kickass.to | 7 | 77.32 KB | 72.69 KB (6.00%) | 34.07 KB (55.94%) |
| 83. google.com.au | — | — | — | — |
| 84. thepiratebay.se | 3 | 11.14 KB | 10.62 KB (4.69%) | 6.55 KB (41.16%) |
| 85. netflix.com | 6 | 113.05 KB | 103.09 KB (8.82%) | 76.23 KB (32.57%) |
| 86. akamaihd.net | — | — | — | — |
| 87. google.pl | — | — | — | — |
| 88. ebay.de | 105 | 1.87 MB | 1.75 MB (6.35%) | 1.52 MB (18.71%) |
| 89. chinadaily.com.cn | 54 | 1.41 MB | 1.23 MB (12.27%) | 1.01 MB (28.10%) |
| 90. dailymotion.com | 63 | 477.83 KB | 463.58 KB (2.98%) | 459.33 KB (3.87%) |
| 91. clkmon.com | 2 | 5.88 KB | 5.86 KB (0.37%) | 3.38 KB (42.52%) |
| 92. about.com | 93 | 2.09 MB | 1.91 MB (8.55%) | 1.65 MB (21.08%) |
| 93. google.com.hk | — | — | — | — |
| 94. gmw.cn | 49 | 469.45 KB | 294.29 KB (37.31%) | 342.63 KB (27.01%) |
| 95. dailymail.co.uk | 517 | 8.21 MB | 7.58 MB (7.65%) | 7.03 MB (14.35%) |
| 96. bp.blogspot.com | — | — | — | — |
| 97. rakuten.co.jp | 469 | 5.37 MB | 3.95 MB (26.37%) | 2.35 MB (56.17%) |
| 98. xnxx.com | 194 | 1.53 MB | 1.49 MB (2.61%) | 1.37 MB (10.99%) |
| 99. alipay.com | 9 | 827.20 KB | 769.70 KB (6.95%) | 514.28 KB (37.83%) |
| 100. vimeo.com | 26 | 366.48 KB | 362.88 KB (0.98%) | 334.02 KB (8.86%) |
This is awesome.These are all great tips for someone with a bit higher skill level.
For more information: http://www.labstech.org/optimizing-images-website-2014-05-20/