Your inputs
Enter values from the same reporting or planning period. Grey placeholders are worked-example inputs, not benchmarks. All money values use the selected currency; no conversion is performed.
Your results
Enter your inputs and press Calculate to see results.
Formula and method
Profit = affiliate earnings − cost. ROI = profit ÷ cost × 100. Return per currency unit = earnings ÷ cost. Compare earnings with cost for break-even status.
Worked example
£300 earnings and £200 cost leave £100 profit, 50% ROI and £1.50 earnings per £1 spent. £100 earnings against the same cost gives a £100 loss and −50% ROI.
How to interpret your results
Return per unit is gross earnings divided by spend; ROI uses profit after that spend. A return of 1.50 is therefore 50% ROI, not 150% ROI.
Assumptions and edge cases
Include all costs relevant to the chosen period. No tax, unpaid time or additional overhead is inferred. With zero cost the cash difference remains valid but ROI and return per unit are undefined.
Related calculators
Programme research
Read official terms and research dates in the programme directory. Enter your own documented assumptions here; recurring or tiered terms require a model with an appropriate scope.
View the programme directoryFrequently asked questions
What does break-even mean here?
Entered earnings equal entered costs. It does not claim that unentered costs have been recovered.