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Growth
Viral Coefficient Calculator
Calculate K — the make-or-break metric for viral growth.
Inputs
%
days
Result
Viral coefficient (K)
0.50
Sub-viral
New users per cycle
500
Cycle length
14 days
About this tool
K = invites per user × invite conversion rate. Above 1 means self-sustaining growth. Below 1 means you need paid acquisition.
What it does
- •Instant K calculation
- •New users per cycle
- •Viral cycle length
- •Growth self-sustaining flag
Use cases
- ★Consumer product growth
- ★Referral loop design
- ★PLG planning
FAQ
What K means what?
K ≥ 1 = viral (self-sustaining); 0.5–1 = amplifying paid growth; < 0.5 = little viral effect.
How do I improve K?
Increase invites per user (better prompts, incentives) and/or conversion rate (better landing pages).