Not all great content goes viral, but (with the exception of awesomely terrible videos) content that does go viral is great. No one can guarantee that any piece of content will take the web by storm, but we can make sure that a piece of content has what it takes.

Long-time citizens of the web can often tell from a first-reading or viewing that a piece is going to explode, but why? Opinions about what it takes to be viral are easy to come by, but let’s look at the facts with data to prove it.

Write long, in-depth posts

In a scientific, statistical look at what makes content most shareable online, two University of Pennsylvania professors looked at the New York Times’ most emailed list to see if they could determine what cause people to share article. You can download the entire PDF here.

The first finding is that longer articles tend to be shared far more often. The correlation remains strong even after taking the amount of site exposure into account. In fact, sheer word count was more closely correlated with sharing than any other variable examined. John Doherty found a similar correlation this past October, finding that long posts receive more than their fair share of links.

Correlation isn’t causation (sorry, the phrase is cliché for a reason), and it’s possible that there’s something else at work here. Perhaps the journalists tend to write longer pieces when they’re writing on hot topics, for example.

A causal relationship makes sense, though. I’m far more likely to email or tweet something from #longreads or /r/DepthHub than a 200-word summary on the same topic. Long posts have the potential to be immersive and thorough in a way that’s impossible for short pieces. If I care about the topic at all, I don’t want to share an article with friends or readers if it just skims over the surface. If you want your word to spread, cover the topic fully.

Long posts aren’t all flowers and sunshine though. While long posts appear more likely to be shared through email and links, a separate study on blog comments found that users are less likely to comment on long posts.

Inspire anger, awe, or anxiety

You won’t be surprised to learn that posts that spend a lot of time on the home page are more likely to go viral, but after adjusting for variables the study does a pretty good job of showing which emotions make a post more viral:

Content that inspires low-energy emotions like sadness is less likely to be shared, where content that inspires high-energy emotions like awe, anger, and anxiety is far more likely to be shared.

Anger wins the award as the most viral emotion studied. Before belittling and insulting your readers, note that anger is typically directed at the topic – not the author or publication. Inciting anger in readers typically requires some tolerance for dealing with controversial topics. The comment study also found that controversial blog posts receive twice as many comments on average. Still, many brands will want to avoid hot topics that could alienate customers and partners.

For most, awe will be the safest and most reliable path towards viral content. Awe is more than surprise – it’s the reason we can’t stop watching movies with big explosions and larger-than-life heroes. Creative inventions, completed labor-intensive projects, stunning design, and novel are all ways to fill viewers and readers with awe.

Prove you care

Emotion-filled posts tend to be shared more, according to the survey. Creating content with an emotional tone can be harder than it sounds, especially in professional writing. This has always been a weakness of mine – I don’t write my emotions, even on topics I am freakishly passionate about. Overly-professional and mechanical corporate writing does not get shared.

There are piles and piles of good, insightful, thoughtful content that no one ever cared about – much of it was just too damn bland. If you need inspiration, look to Ian Lurie for examples of writing that no one would consider bland. (That’s a compliment, I swear.)

Practically useful, surprising, and interesting

Content that is surprising, interesting, and practically useful receives more shares than the obvious, boring, and useless content. These might be the most intuitive of the findings, but it’s helpful to keep in mind the degree to which each variable impacts sharing.

Known authors

Being known by the audience had a large impact on whether a news article was shared. In fact, the fame of the author was just slightly more important that content that was surprising. Luke Clum recently said it best on the Distilled blog:

“…a common misconception has developed amongst SEO’s – mainly that good content speaks entirely for itself. While content is innately influential, it usually only carries the authority of its creator or publisher.” (source)

SEOs are experts in detecting credible content online, yet we sometimes forget that every piece of content is at least partly considered based on its author’s reputation – or lack thereof – and credibility. If a piece of content is intended to go viral, an industry authority (aspiring or current) will usually be better off taking charge of it. Otherwise, content may need to make a special effort to inspire trust (e.g. through introduction and stories).

Female authors

The NYT study also suggests that female authors had a greater chance of going viral, but the underlying reasons are unclear. Do women choose more viral topics than men? Is the Times better at hiring female journalists? We may never know.

The easy answer: humor

Most obviously, content that is truly and broadly viral is almost always funny. One study interestingly titled “From subservient chickens to brawny men” found that despite 62% of ads being aired by Fortune 500 companies, 60% of viral ads were being generated by the smaller companies. The discussion continues:

“Humor was employed at near unanimous levels for all viral advertisements. Consequently, this study identified humor as the universal appeal for making content viral.”

Humor isn't always the answer, but it's essentially a pre-requisite for a viral ad. Small companies win more than their share of attention because they're willing to be a little more interesting and less sterile. Take Mike Pantoliano’s advice: shut up and be funny. 

Limitations

As I’ve said, these studies looked at correlation (which is not necessarily causation). Further, quantifying human response is enormously difficult, and not everyone is the same. I am by no means suggesting that the viral checklist is applicable to every single person on the planet. Still, I’m pretty comfortable with the research behind the checklist, and it passes the common-sense test.

A viral checklist

Two months from now it’s going to be easy to sit down and create content in the same habits we always have. Not all content needs to be viral, but when that’s the goal, make sure that you accomplish all of the following.

• Did you sufficiently cover the topic? Is it long enough? (24)
• Does the content inspire a high-energy emotion like awe (16), anger(18), or anxiety (18)?
• Did your tone convey emotion? (12)
• Is it practically useful? (16)
• Is it interesting? (14)
• Is it surprising? (8)
• Does the author have fame/credibility? (8)
• If it’s supposed to be funny, is it actually funny? Are you sure your friends aren’t just being nice? (∞)

You can’t always have all of these factors, so I've added a maximum score in parenthesis to help prioritize those factors that research has shown to be most important to sharing. If you rate your content at or near 100, it's likely that it has a far greater chance of going viral.