METHOD & GUIDANCE
How this calculation works
Enter figures from the same period and on a consistent VAT-inclusive or VAT-exclusive basis. Tool IQ recalculates every output immediately; nothing you enter is saved or sent to us.
How to use the result
Reconcile every recurring-revenue movement, then distinguish acquisition-led growth from retention and expansion in the existing customer base.
Worked example
The opening example starts at 50,000 MRR, adds 11,000 from new and expansion, and loses 6,000 to contraction and churn, ending at 55,000.
Common mistakes
- Including one-off service revenue in MRR.
- Counting reactivation in more than one movement.
- Using bookings before the revenue becomes recurring.
Frequently asked questions
Is this calculator free?
Yes. It requires no account and stores no calculation inputs.
Can I use the answer for a formal filing?
No. It is a planning estimate, not accounting, tax, legal or investment advice. Confirm material decisions with a qualified professional.
Should I include VAT?
Use a consistent basis throughout. Businesses that recover input tax commonly model net figures; consumer-facing prices are often considered gross.
Continue the decision
- Customer Churn Calculator — Measure customer churn, retention and net movement.
- Revenue Growth Calculator — Measure growth and project a future revenue scenario.
Method reviewed 26 July 2026. Figures are illustrative and calculated locally in your browser.