K-Factor Calculator

Calculate K-factor with cycle time for viral growth modeling. Advanced viral coefficient calculator.

K-Factor
kFactor
Viral coefficient
Viral Cycles
cycles
Number of complete cycles
Projected Total Users
projectedUsers
Users after time period
Growth Multiple
growthMultiple
Total growth multiplier
💡 K-Factor Insights
• K-factor and cycle time determine viral growth rate
• Shorter cycle time accelerates growth even with lower K
• K = 0.5 with 3-day cycle can outgrow K = 0.8 with 21-day cycle
• Optimize both K-factor and cycle speed
• PayPal and Dropbox achieved K greater than 1 with incentives

K-Factor with Cycle Time

K-factor combined with viral cycle time determines total viral growth velocity.

K-Factor Formula

K = Invitations Per User × Conversion Rate

Viral Growth Formula

Users(t) = Initial Users × (1 + K) ^ Cycles

The Power of Short Cycle Times

Cycle time is the period from user activation to their referrals activating. Shorter cycles mean more compounding:

  • 2-day cycle: 15 cycles per month
  • 7-day cycle: 4 cycles per month
  • 30-day cycle: 1 cycle per month

With K = 0.6: 2-day cycle gives 200x growth in 90 days, while 30-day cycle gives only 4x growth.

Example

App with 100 users, K = 0.8, 7-day cycle, 30-day projection:

  • Cycles in 30 days: 4
  • Growth per cycle: 1.8x
  • Total users: 100 × 1.8^4 = 1,050 users
  • 10.5x growth in one month

Frequently Asked Questions

How does cycle time affect viral growth?

Cycle time is time from user signup to their referrals signing up. Shorter cycles compound growth faster. Example: K = 0.6 with 5-day cycle = 30 cycles in 150 days = massive growth. Same K with 30-day cycle = only 5 cycles = much slower. Reduce cycle time by: faster onboarding, immediate sharing prompts, instant invite delivery, quick activation.

What is the relationship between K-factor and cycle time?

Viral growth rate = K-factor / Cycle time. Both matter equally. K = 0.5 with 2-day cycle (0.25 daily growth rate) beats K = 1.0 with 10-day cycle (0.10 daily rate). Optimize both: increase K through better conversion and more invites, decrease cycle time through faster onboarding and immediate sharing prompts.

How do I model viral growth over time?

Viral growth formula: Users(t) = Initial users × (1 + K) ^ Cycles. Example: 100 users, K = 0.8, 5-day cycle, 30-day period = 6 cycles. Users = 100 × (1.8) ^ 6 = 3,430 users. For K less than 1, growth slows over time. For K greater than 1, growth accelerates exponentially. Monitor actual vs projected to validate assumptions.

Related Calculators

Viral Coefficient Calculator

Basic viral coefficient

Referral Marketing ROI

Referral program ROI

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