Tech Debt Interest
Estimate how much extra repair time a shortcut can create later.
Payoff hours = initial fix × (1 + effective growth)^months. Effective growth compounds with code velocity — more features landing on the hack accelerate the drag.
Part of: Saving & Spending Calculators
How to use
- Enter Initial Fix Hours and Monthly Growth %.
- Set Code Velocity — new features built on top per month.
- Set how many months you plan to wait before paying it down.
- The heatmap shades each month by maintenance burden band.
Examples
Before you trust the result
Check the inputs that matter most: dates, rates, units, costs, and any optional fields you skipped. A calculator can only work with the numbers entered here, so use the result as a decision check rather than a final answer when money, health, tax, legal, or safety consequences are involved.
If the result feels surprising, change one input at a time and watch which number moves. That usually shows the real lever behind the decision.
Next up
Frequently asked questions
› What is a good growth rate? Definition
5–10%/mo for actively-developed modules; near 0 for stable utilities. High-churn areas compound fastest.
› Is this an exact estimate? Trust & accuracy
No — it is an order-of-magnitude tool to force the conversation about scheduling repayment.
Tips & related reading
See the Saving & Spending Calculators hub →Tips & how-tos
Relevant links
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