WebPageTest results

Summary

Performance data
First view Repeat view
Page Speed index First byte Start render Load Bytes Requests Connections Speed index Load
Times are in milliseconds and are the median values from 1 runs in WebPageTest. The test location was Dulles, the connection was Native Connection and the browser was Chrome. All measurements were taken between 13:05:56 and 13:24:07 on Monday, June 01, 2015.
Nature homepage 2,514 1,731 2,496 3,200 366,202 57 30 832 1,275
Nature article 2,134 1,053 1,992 3,370 913,926 76 36 1,701 2,536
CNN homepage 3,741 126 2,891 6,624 1,999,412 128 72 2,479 4,734
CNN article 5,982 2,256 4,292 9,794 2,697,489 188 105 2,547 6,414

Care should be taken when making comparisons between the figures for different pages, since each page contains a different amount of data and requires a different amount of work. Nonetheless, some comparisons can be made.

Charts

Speed index, first view

Speed index, first view Nature article 2,134 Nature article Nature homepage 2,514 Nature homepage CNN homepage 3,741 CNN homepage CNN article 5,982 CNN article First-view speed index (lower is better)

Speed index, repeat view

Speed index, repeat view Nature homepage 832 Nature homepage Nature article 1,701 Nature article CNN homepage 2,479 CNN homepage CNN article 2,547 CNN article Repeat-view speed index (lower is better)

Speed index, repeat-view improvement

Speed index, repeat-view improvement Nature homepage 33% Nature homepage CNN article 43% CNN article CNN homepage 66% CNN homepage Nature article 80% Nature article Repeat-view speed index as a percentage of first-view (lower is better)

First byte

First byte CNN homepage 126 CNN homepage Nature article 1,053 Nature article Nature homepage 1,731 Nature homepage CNN article 2,256 CNN article Time to first byte (milliseconds)

Start render, difference from first byte

Start render, difference from first byte Nature homepage 765 Nature homepage Nature article 939 Nature article CNN article 2,036 CNN article CNN homepage 2,765 CNN homepage Time from first byte until start render (milliseconds)

Load, difference from first byte

Load, difference from first byte Nature homepage 1,469 Nature homepage Nature article 2,317 Nature article CNN homepage 6,498 CNN homepage CNN article 7,538 CNN article Time from first byte until load event (milliseconds)

Optimisations

Performance optimisations
Page First byte Persistent connections GZIP compression Image compression Progressive JPEGs Browser caching Asset CDN
Nature homepage 0% 95% 100% 79% 0% 37% 58%
Nature article 5% 96% 100% 64% 9% 48% 52%
CNN homepage 98% 100% 96% 78% 13% 51% 90%
CNN article 0% 92% 99% 62% 0% 45% 84%