The PR BlogDigital PRSocial Media ManagementHow To Build a Viral Loop (Using Mathematics)

How To Build a Viral Loop (Using Mathematics)

It's satisfying to build viral loops, but it's also hard as hell.

Cover photo by Jerry Silfwer (Instagram)

Knowing how to engineer a viral loop is a PR superpower.

In this article, I’ll run the numbers of a viral loop to help you construct your traffic-generating machines.

As a digital strategist, I’ve designed many viral loops to gain traction and generate leads for B2C and B2B brands. Viral loops are powerful, but they also break easily.

Here we go:

How To Determine Virality

Let’s say you post a hilarious cat video on YouTube.

You share your cat video across social media and get your first 1,000 views. Out of those 1,000 viewers, 10% (100 people) decide to share your cat video with their friends — once on average. Each such share generates 11 new video views, a total of 1,100.

Going from 1,000 views (1st cycle) to 1,100 unique views (2nd cycle) equals a viral coefficient of 1,1.

And anything above 1,0 = viral, woohoo!

How many views will you get in the 3rd cycle? Out of the 1,100 people in the 2nd cycle, 10% will share it once, generating on average 11 new views per share and—boom!—you get 1,210 (1,100 x viral coefficient) additional views after the 3rd cycle.

Look at your cat video now, oh mighty Viral Loop Designer!

But before we get ahead of ourselves, let’s examine the inner workings of a viral loop.

Viral Loop Weaknesses

Why aren’t all spin doctors involved in designing viral loops? Well, as it turns out — it’s challenging to get viral loops to work.

Here are some variables to consider:

Population Size

We can only expect your content to perform as long as you reach your target audience. Cat videos have an extensive appeal across demographics, so your population size will be enormous!

But most businesses have very little to do with cats.

For instance, if you’re a CRM SaaS company, you’ll probably struggle to reach critical mass for your cycles.

Loop Instability

By calculating averages within each cycle, you might find somewhat stable inputs for click-through rates (CTR), conversion rates, social back traffic, etc.

But in reality, these indicators are volatile, and they fluctuate immensely from cycle to cycle.

Getting your 2nd cycle to perform above 1,0 (viral coefficient) is often a challenge, and it gets more complicated with each cycle.

Engagement Distribution

A key factor is social back traffic from people sharing your content.

This average traffic number can be deceiving; most shares hardly result in any back traffic. It’s often sharing that keeps the average up.

The Engagement Pyramid

The 1% rule of online engagement was mainly an urban legend on the internet. Still, a peer-reviewed paper from 2014 entitled The 1% Rule in Four Digital Health Social Networks: An Observational Study confirmed the 1% rule of thumb.

Engaged publics typically distribute themselves according to a distribution that has been scientifically proven well before the advent of the internet and social media, and supporting sociologists have made observations for centuries.

The engagement pyramid divides publics into three distinct groups:

  • Creators
  • Contributors
  • Lurkers

When studying internet forums specifically, it’s not uncommon to find that 90% of users have never posted (lurkers), 9% are adding only to existing topics and threads (contributors), and 1% are actively starting new subjects and threads (creators).

The engagement pyramid is sometimes called the 1% rule or the 1-9-90 rule.

Read also: The Engagement Pyramid

Creators and contributors tend to interact more, so you’re likely to run out of shares much more quickly than social shares from lurkers.

Cycle Times

YouTube is very friendly to viral mechanics:

You watch a short video, share it, and the next cycle kicks in — often in minutes. Actually, from a mathematical standpoint (see mathematical formula), cycle time truly matters more than social back traffic averages!

If you need someone to review a 30-page whitepaper on SlideShare before being ready to share the content, you might be facing an average cycle time of several hours (or even days).

Reducing viral loop cycle time has, by far, the most significant effect on viral growth.

External Factors

Your cat video isn’t the only social object competing for people’s attention. It’s impossible to fully control or anticipate what content will compete for attention at any given time.

We’re dealing with chaos theory here: There are too many unknown variables to find, understand, and compute, from the anatomy of complex networks to the slightest details affecting individual behaviour.

Content Quality

Producing content that inspires the kind of math discussed above is quite challenging. With unlimited marketing budgets, you might be able to enrol a team of world-class creatives with an organization of production professionals to match. But there are no guarantees.

Hundreds of thousands of talented (or lucky) people are launching attempts at viral content every day. Can you be sure to beat them all at a time of your choosing?

Still hungry for viral success? What we want is to apply the viral loop to business.

Viral Project Economics

We could go on to create a “cat video,” meaning a video that’s cute and funny to a large number of people and thus aim for the same math as described above and, for the sake of argument, reach 1,000,000 views on YouTube.

If the total production cost (including promotion costs) is $250,000 and the company’s average profit margin is $50 per unit sold, a 1,000,000-view video that converts new customers at 0,01% (not uncommon) will generate $5,000. And that is not great for a $250,000 video.

Also, if the business can manage 1,000,000 video views on YouTube, how can anyone be sure that everyone watching is potential customers — and nothing else? There are other ways for a viral video to create value beyond direct sales:

  • Brand value
  • Brand awareness
  • Audience growth
  • Employer branding
  • Data harvesting (audience analytics)
  • Email list building

Still, “money in the bank” should always be an essential consideration. And there’s always the chance that your viral mechanics fail.

Boosting Your Viral Loop

We’ll need all the help we can get. Let’s explore a quick overview of helpful viral tools:

Seed traffic. The 1st wave of traffic you generate, either by activating your existing audience, through influencer outreach, or advertising. (Must reach critical mass for the viral effects to be given a chance to come into effect.)

Landing page. A page designed specifically to harvest a specific intent. Typical for landing pages is that they only have one call-to-action (CTA).

Definition of a Landing Page

Landing page (LP) = a web page stripped of standardised menus and sidebars with a single call-to-action often repeated as the users scroll further down the page.

Read also: Iceberg Publishing — The Cool Way to Grow Traffic and Conversions

Lead magnet. “Free” online content encourages potential customers to opt in. Efficient lead magnets target urgent needs that can be relieved quickly. (Also known as “opt-in bribes.”)

Uptick page. If you can get a person to take action, you’ve “primed” them. So, instead of letting them go, you can refer them to an uptick page where you can make an additional ask of them.

Uptick bonus. Lead magnets tailored explicitly for specific content types are often called “content upgrades”.

Referral engine. Often combined with uptick pages, referral engines encourage users to share more than once, often using a generator for unique URL addresses.

If you’re looking for ready-made tools, LeadPages with templates for high-converting landing pages could be a place to start. If you’re looking for uptick pages with built-in referral engines, check out UpViral.

Viral Loops Step-by-Step

Let’s build an imaginary viral loop for the Doctor Spin blog, shall we?

Step 1. The seed traffic (some Facebook ads targeted at a lookalike audience based on existing email subscribers) is directed to a landing page. If your brand already has critical mass, that helps, too.

Step 2. The traffic is offered a “free” (in exchange for their email addresses) lead magnet (a three-day video course that targets an urgent pain point, like “How to Succeed with Content Marketing in B2B”). Three consecutive videos allow for three separate uptick pages.

Step 3. On the 1st uptick page, the converted users get the first video and are incentivized to share my landing page with an uptick bonus (“Free Templates for Creating High-Converting Blog Posts and Landing Pages for B2B”). In this example, the user will get the bonus by referring at least three friends to the initial landing page. A referral engine, generating unique URLs for each user, keeps track.

Step 4. On day two, I use their email addresses to remind all signups that the following video is live on the 2nd uptick page. Once there, they are reminded again to share the uptick bonus.

Step 5. On day three, I again remind the signups via email that the final video is live on the 3rd uptick page. Once there, they are reminded to share the uptick bonus a third time.

For the sake of argument, let’s say that I send 1,000 potential customers to my lead page, converting at 40%, in turn sending 400 people to the uptick pages converting at an average of 20%. The most active users like the videos and the uptick bonus (I hope!) enough to share them 1,5 times on average at 10 new landing page visitors per share.

  • 1st cycle: 1,000 targeted visitors, 400 new subscribers.
  • 2nd cycle: 1,200 targeted visitors, 480 new subscribers.
  • 3rd cycle: 1,440 targeted visitors, 576 new subscribers.

And so on.

Non-Viral Loops Have Value, Too

No viral loop lasts forever, of course. But hopefully, this theoretical experiment demonstrates the raw power of viral loops. Three uptick pages are presented sequentially using a landing page, an email reminder function, a referral engine with unique URLs, a lead magnet, and an uptick bonus.

When dealing with small population sizes (often for niched products or services), you must make sure to sustain your viral loop.

My favourite viral loop is that of Instagram:

When you take a picture, Instagram allows you to edit and apply various filters. When you engage in this activity, you become creatively more attached to the image — it becomes more than a picture; it becomes something you’ve created. Social networks are viral specialists. It’s in their DNA, their business, to activate online users. Doing it yourself for your business can be daunting.

Even if you only manage to establish a viral coefficient of 0,5 (and only keep it for a few cycles), these conversions might still make a big difference to your initial marketing effort — remember the seed traffic?

Using Facebook Ads to pay for 1,000 click-throughs and adding a “0,5 loop” will considerably increase your ROI for the initial ad buy. There’s no “free traffic,” but this is close.

Example (“0,46” loop):

  • Seed traffic: 1,000 views
  • Lead page conversion: 32%
  • Uptick page traffic: 320
  • Uptick bonus conversion: 16%
  • No. of referrers: 51,2
  • Shares per referrer: 1,4
  • Total no. of shares: 71,68
  • Social back traffic per referral: 6,5
  • 1st cycle traffic: 465,2 views (“free traffic”)
  • Viral coefficient: 0,46

In reality, for your type of business, transforming an existing “0,5 loop” into a “1,1 loop” might be near impossible (and expensive).

However, adding “0,5 loops” here and there might be straightforward and cost-efficient — while doubling your marketing ROI. The viral effect isn’t a binary phenomenon. Instead of thinking of a “0,5 loop” as a failed viral loop, you should think of it as an online marketing amplifier.

Not bad for a funny cat video.

Thank you for reading this article. Please consider supporting my work by sharing it with other PR- and communication professionals. For questions or PR support, contact me via [email protected].

Jerry Silfwer
Jerry Silfwer
Jerry Silfwer, alias Doctor Spin, is an awarded senior adviser specialising in public relations and digital strategy. Currently CEO at KIX Index and Spin Factory. Before that, he worked at Kaufmann, Whispr Group, Springtime PR, and Spotlight PR. Based in Stockholm, Sweden.



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