Facebook is cracking down on articles which have eye-catching headlines but very little substance. So-called 'clickbait' posts end up being displayed higher in users news feed because they rack up lots of clicks.

The social media site says it will now use software to see how long users spend looking at articles in order to work out if they are actually interesting.

The website says it is also going to introduce an update to help people see links shared in the best format.

Facebook says that when they asked people in a survey what type of content they preferred to see in their news feeds, 80% of the time people preferred headlines that helped them decide if they wanted to read the full article before they had to click through.

"Over time, stories with 'click-bait' headlines can drown out content from friends and Pages that people really care about," Facebook says.

The site says one way to tackle this problem is to look at how long people spend reading an article away from Facebook.

"If people click on an article and spend time reading it, it suggests they clicked through to something valuable. If they click through to a link and then come straight back to Facebook, it suggests that they didn't find something that they wanted."

"With this update we will start taking into account whether people tend to spend time away from Facebook after clicking a link, or whether they tend to come straight back to News Feed when we rank stories with links in them," it says.

And in terms of link-sharing, the site says people often prefer to click on links that are displayed in the link format (which appears when you paste a link while drafting a post), rather than links that are buried in photo captions.

Users do not want links like this | Image: Facebook

"The link format shows some additional information associated with the link, such as the beginning of the article, which makes it easier for someone to decide if they want to click through. This format also makes it easier for someone to click through on mobile devices, which have a smaller screen," Facebook says.

The site says it will now prioritise showing links in the link-format, and show fewer links shared in captions or status updates.

"The best way to share a link after these updates will be to use the link format," it adds.