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Checkpoint 14 - Online files must be optimised

Conformance: Desirable


All web resources and assets should be optimised for performance. This includes images, stylesheets, scripts, PDF, and PowerPoint.

Benefits of conformance

  • Optimisation of assets ensures smaller file sizes and fewer HTTP requests for faster downloading of pages.
  • Responsive web experience for all users, including those with low bandwidth fixed or mobile internet access.

Risks of non-conformance

  • Increased download times due to larger file sizes.
  • Possible migration to other, more expensive channels due to slow response times.

Implementation advice


There are many ways to optimise web resources for online delivery; some key areas of focus are:

  • keeping markup as lean as possible
  • reducing the number of HTTP requests required for each page by combining asset files where possible
  • reducing asset size by minifying and/or compressing file contents
  • ensuring assets are cacheable by optimising server configuration
  • sharing central assets to reduce redundant downloads of identical assets.

The supporting information for this checkpoint provides more information about how to optimise for online delivery.

Last reviewed
01 April 2011
Last updated
11 April 2011