Google is rolling out an update to its search algorithm that will penalise websites that have not been optimised for viewing on mobile devices such as smartphones or tablets.
First announced in February, Google said that the algorithm change will affect mobile searches in all languages worldwide and will have a significant impact on its search results.
"As people increasingly search on their mobile devices, we want to make sure they can find content that’s not only relevant and timely, but also easy to read and interact with on smaller mobile screens," a Google spokesperson said.
"Starting April 21, we’ll use a web page's 'mobile-friendliness' as one of many factors to help rank searches done on mobile devices."
Google has been offering resources for webmasters to test their mobile sites and tools to make their pages more mobile-friendly since February. Companies and individuals can check whether their website is classed as mobile-friendly by entering the web address here.
However, some webmasters have still been caught caught short.
According to research compiled by mobile marketing firm Somo, websites that will be punished by Google under the new update include the official website of the British Monarchy, David Beckham's official site, Nintendo, Versace, Next, Channel 4 and the Daily Mail.
Although several of these brands do have apps or mobile sites, they still risk dropped rankings as Google does not recognise them as "mobile-friendly", according to Somo.
Separate research by The Search Agency UK revealed that only 32 of the FTSE 100 websites use 'responsive' web design, whereby a site automatically adjusts its scale based on the size of the browser window or device screen. This is regarded as the industry best practice.
A further 29 FTSE 100 websites have mobile-dedicated sites, but 39 have no mobile-friendly site at all, risking significant impact on their search rankings.
“Google's upcoming ‘mobile friendly’ algorithm update – the so-called Mobilegeddon – is another indication of how important mobile search is and will be this year," said Maria Mitsostergiou, head of search at Somo.
"The incorporation of 'mobile friendliness' as a ranking signal for websites will separate companies proactively opting-into mobile versus those that cannot see the benefit and power of their mobile presence on search engine results pages."
Adults in the UK will spend more time on mobile devices than desktop computers in 2015, according to research from eMarketer, spending an average of 2 hours 26 minutes a day on mobile devices compared to 2 hours 13 minutes on a desktop.
The company also predicts that mobile search will surpass desktop in 2015, with the majority of ad spend, organic traffic and paid clicks coming from smartphones and tablets.
Telegraph Media Group Limited 
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