The Liberal Democrats’ website came in a close second, and there was a substantial drop to the Conservative Party site. UKIP and the Green Party came in joint last.
Digital marketing agency Quirk London analysed the websites of the five parties in March, assessing the key components that make a website user friendly.
The Labour Party scored very highly for its approach to usability (81 per cent), and it was seen as the most visually appealing. Quirk said the content was easy to digest, clearly prioritised and relatively easy to find. However, the homepage did not offer a clear value proposition to vote Labour, the researchers found, and it was slim on policy detail.
Its error page was described as offering some humour with the statement: "Well, this is rotten. But, a 404 Error is still better than five more years of Tory government."
The Liberal Democrat website scored 78 per cent but was let down by its homepage and overall layout and visual design, according to the analysis. Quirk described the website as a little "busy" with too much content, but said the site performed well overall for usability.
The Conservative Party (61 per cent) suffered from information overkill on the homepage. Forcing visitors to sign in, share or provide contact details when viewing anything of real value, detracted from what should be a simple process, argued Quirk.
The Green Party achieved the lowest score alongside UKIP (53 per cent), suffering from poor page layout and visual design in particular. UKIP’s website navigation made it challenging to find the party’s policies, and once found, they were limited to a single page of plain text that made scanning for headline issues challenging.
Richard Palmer, director and user experience lead at Quirk London, said: "Regardless of how nice a website looks, if it doesn’t answer the needs of its audience, it retains little value for anyone."
Quirk undertook the research using a standard questionnaire, equally grading the following categories: homepage; task orientation; navigation and information architecture; writing and content quality; page layout and visual design; and search, help and feedback.