Enter Campaign Inputs
The page stays single-column, while the calculator fields use responsive three, two, and one-column layouts.
Example Data Table
| Campaign | Customers | Invites/User | Open Rate | Click Rate | Landing Signup | Activation | K |
|---|---|---|---|---|---|---|---|
| Creator Referral Push | 1200 | 4.2 | 58% | 31% | 24% | 68% | 0.13 |
| Product Hunt Follow-up | 800 | 6 | 64% | 38% | 29% | 71% | 0.30 |
| Student Ambassador Loop | 450 | 7.5 | 72% | 42% | 33% | 76% | 0.57 |
| Freemium Upsell Referral | 2200 | 3.1 | 49% | 27% | 21% | 63% | 0.06 |
Formula Used
Invite conversion rate
Invite Conversion = Open Rate × Click Rate × Landing Signup Rate × Activation Rate
Viral coefficient
K = Average Invites per Customer × Invite Conversion Rate
Retention adjusted coefficient
Effective K = K × Retention Rate
Projection logic
Next Generation New Users = Previous Generation New Users × Effective K + Organic Assist Users
Financial outputs
Revenue per Cycle = New Users × Revenue per Active New User
Cost per Cycle = (New Users × Incentive Cost) + Fixed Cycle Cost
ROI = ((Cumulative Revenue − Cumulative Cost) ÷ Cumulative Cost) × 100
How to Use This Calculator
- Enter your current customer base and average invites per customer.
- Fill in each funnel stage rate from open to activation.
- Add retention so future referral generations stay realistic.
- Set projection generations and the referral cycle length.
- Enter revenue, per-user incentive cost, and fixed cycle cost.
- Optionally include organic assist users gained each cycle.
- Click the calculate button to show results above the form.
- Review the graph, table, ROI, and export your CSV or PDF.
Frequently Asked Questions
What does viral coefficient mean?
It measures how many new users one existing user generates through referrals. A value above 1 means growth can sustain itself without constant paid acquisition.
Is a value below 1 always bad?
No. Many healthy campaigns run below 1 and still perform well when retention, monetization, or paid support are strong. It simply means the loop is not fully self-propelling.
Why include retention in this tool?
Retention shows how many newly acquired users remain active enough to refer others later. It helps estimate effective loop strength across future generations.
What counts as invite conversion?
Here it means the full path from invite open to click, landing page conversion, and final activation. It reflects the quality of your entire referral funnel.
How many generations should I model?
Five to ten generations is usually enough for planning. Shorter ranges help campaign reviews, while longer ranges show how small conversion changes compound over time.
Can this replace cohort analysis?
No. It is a planning calculator, not a cohort analytics replacement. Use it for scenario modeling, then validate assumptions with actual product and campaign data.
What improves viral coefficient fastest?
Usually better invite volume, stronger message relevance, higher landing page conversion, and smoother activation. Small gains at every step often beat one large change.
Should I optimize K or revenue first?
Optimize both together. A higher coefficient matters most when acquired users retain, monetize, and cost less to activate than the revenue they produce.