Free Tool

Viral Coefficient Calculator

Calculate your K-factor and see if your product can achieve viral growth.
A viral coefficient above 1.0 means exponential, self-sustaining growth.

How many users do you currently have?

Average number of referrals/invites each user sends

What % of invited people actually sign up?

Days between signup and sending invites (for growth projection)

Measure your viral potential

Enter your metrics to calculate your K-factor and see projected growth over multiple referral cycles.

The viral coefficient formula
K = i × c
invites per user × conversion rate

What is the viral coefficient?

The viral coefficient (K-factor) measures how effectively your users bring in new users through referrals.

<1

K < 1.0

Growth will eventually slow and stop without other acquisition channels. Each user brings in less than one new user.

=1

K = 1.0

Sustainable but linear growth. Each user brings exactly one new user, maintaining your user base.

>1

K > 1.0

Exponential viral growth! Each user brings more than one new user, creating a self-sustaining growth loop.

How to increase your viral coefficient

Make sharing effortless

Add one-click share buttons, pre-written messages, and unique referral links. The easier it is to share, the more people will do it.

Incentivize referrals

Offer rewards for successful referrals—early access, discounts, premium features, or priority in your waitlist.

Create FOMO

Show waitlist position, display how many people are ahead, and reward users who move up by referring friends.

Track and optimize

Monitor which channels and messages drive the most referrals. Double down on what works.

Build viral referral loops

Waitlister has built-in referral tracking, unique referral links, and milestone rewards to help you achieve viral growth.

Do not sleep on this tool. I can have a CTA page up in 10-15 mins that encourages others to share via a soft referral system.
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DigitalGrowthHacksClub
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