How do I calculate K-factor (Viral coefficient)?

Use the formula(s) on this page. Keep inputs consistent by period and basis.

What are good benchmarks?

Benchmarks vary by model and stage. See Benchmarks on this page for ranges.

Inconsistent definitions/time windows; wrong basis (revenue vs gross profit).

Pitchkit

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GLOSSARY

K-factor (Viral coefficient)

Number of new users each existing user brings in.

Why it matters

K > 1 means exponential organic growth. Even K = 0.3-0.5 meaningfully reduces CAC.

Worked example

Each user sends 5 invites; 20% convert → K = 5 x 0.2 = 1.0 (viral breakeven).

Benchmarks

Most B2B SaaS: K = 0.1-0.4. Strong viral products: K = 0.5-1.0+. Sustained K > 1 is rare.

Common pitfalls

Measuring one-time spikes vs sustained virality; not accounting for invite fatigue; ignoring quality of referred users.

Back to Glossary

GLOSSARY

K-factor (Viral coefficient)

Number of new users each existing user brings in.

Why it matters

K > 1 means exponential organic growth. Even K = 0.3-0.5 meaningfully reduces CAC.

Worked example

Each user sends 5 invites; 20% convert → K = 5 x 0.2 = 1.0 (viral breakeven).

Benchmarks

Most B2B SaaS: K = 0.1-0.4. Strong viral products: K = 0.5-1.0+. Sustained K > 1 is rare.

Common pitfalls

Measuring one-time spikes vs sustained virality; not accounting for invite fatigue; ignoring quality of referred users.

K-factor (Viral coefficient)

Why it matters

Worked example

Benchmarks

Common pitfalls

K-factor (Viral coefficient)

Why it matters

Worked example

Benchmarks

Common pitfalls

How to show in your deck

Deck snippet

Formulas

FAQs

Related terms

Why it matters

Worked example

Benchmarks

Common pitfalls

Why it matters

Worked example

Benchmarks

Common pitfalls

How to show in your deck

Deck snippet

Formulas

FAQs

How do I calculate K-factor?

What are good benchmarks?

Common pitfalls?

Related terms