Technical Debt Calculator

Quantify the cost of technical debt from velocity impact, bug rates, and onboarding delays.

Number of developers

Avg developer cost/year ($)

Velocity loss %

Bug fix time %

Base onboarding (weeks)

Annual turnover %

Remediation effort (weeks)

Monthly debt growth %

Tab to move between fields

Annual cost of tech debt

$542,308.00

≈ 13 Teslas

Monthly cost of tech debt

$45,192.00

≈ 4 years of state college

Velocity loss cost / year$300,000.00

Bug fix cost / year$225,000.00

Onboarding penalty / year$17,308.00

Remediation cost$103,846.00

Remediation team size3

Payback period (months)3

2-year net savings$1,017,777.00

Debt cost in 12 months$687,777.00

How to Use This Calculator

Enter the number of Developers and Average Developer Cost per Year.
Set Velocity Loss % and Bug Fix Time % — the portion of sprints lost to tech debt.
Input Base Onboarding Weeks and Annual Turnover % to capture knowledge transfer costs.
Set Estimated Remediation Effort (weeks) and Monthly Debt Growth Rate %.
Review Annual Cost of Tech Debt and Monthly Debt Cost to build the business case for a refactoring investment.

How the result changes with Number of developers

Number of developers: Size of the engineering team affected by tech debt.
Avg developer cost/year ($): Fully-loaded annual cost per developer (salary + benefits + overhead).
Velocity loss %: Percentage of development velocity lost to working around tech debt.
Bug fix time %: Percentage of developer time spent fixing debt-related bugs.
Base onboarding (weeks): Weeks to onboard a new developer in a clean codebase.
Annual turnover %: Yearly developer turnover rate.
Remediation effort (weeks): Estimated calendar weeks to address the major tech debt items.
Monthly debt growth %: Rate at which tech debt compounds monthly if left unaddressed.

Annual cost of tech debt: Total yearly cost from velocity loss, bugs, and onboarding delays.
Monthly cost of tech debt: Monthly drag on the engineering organization.
Velocity loss cost / year: Annual cost of developers working slower due to tech debt.
Bug fix cost / year: Annual cost of fixing debt-induced bugs.
Onboarding penalty / year: Extra cost from extended onboarding for new hires.
Remediation cost: One-time cost to address tech debt with a dedicated team.
Remediation team size: Recommended number of developers for remediation (~30% of team).
Payback period (months): Months until remediation investment pays for itself.
2-year net savings: Net savings over 2 years from remediating now vs. doing nothing.
Debt cost in 12 months: Projected annual debt cost in 12 months if growth continues.

Identify Input Parameters
4 parameters
Number of developers = 10, Avg developer cost/year ($) = 150000, Velocity loss % = 20, Bug fix time % = 15 = 8 input(s) provided
Calculate Annual cost of tech debt
Annual cost of tech debt = velocityLossCostPerYear + bugFixCostPerYear + onboardingPenaltyCost
542308 = $542,308
Calculate Monthly cost of tech debt
Monthly cost of tech debt = annualDebtCost / 12
45192 = $45,192
Calculate Velocity loss cost / year
Velocity loss cost / year = teamCostPerYear * (velocityLossPct / 100)
300000 = $300,000
Calculate Bug fix cost / year
Bug fix cost / year = teamCostPerYear * (bugFixTimePct / 100)
225000 = $225,000