Product Debt Index (PDI)
A diagnostic score ranging from 0 to 100 that quantifies the total technical debt of a software organization in explicit dollar terms. The Product Debt Index translates abstract engineering complexity into measurable carrying costs and valuation drag. It provides a standardized mechanism for product and finance teams to measure the economic penalty of unmanaged software feature accumulation. By establishing a direct link between code entropy and financial performance, the PDI forces accountability in architectural decision-making.
“Technical debt is an engineering problem. Product debt is a balance sheet crisis.”
Traditional technical debt metrics fail because they remain isolated within engineering departments as story points or refactoring tickets. The Product Debt Index bridges this gap by expressing debt as a financial liability on the balance sheet. When executives can see the explicit dollar cost of feature bloat, they allocate resources toward stabilization rather than blind expansion. This metric fundamentally alters how companies evaluate the true cost of their product roadmaps.
Richard Ewing’s Research Thesis
We must measure software complexity in the only language the board understands: dollars.
Why This Specification Exists
Engineering cannot get funding to fix technical debt because executives only see new features as valuable.
Complaining about code quality using story points or technical jargon.
No shared language between engineering realities and financial oversight.
A financial index that quantifies technical debt in terms of enterprise carrying cost.
What Changes If You Believe This?
Refactoring becomes a financially justified priority.
Can accurately measure the ROI of technical debt repayment.
Must account for carrying costs before proposing new features.
Improved baseline quality reduces systemic vulnerabilities.
Recommended Action by Role
Use PDI to defend refactoring budgets to the CFO.
PDI Calculator
Calculates the financial carrying cost of your existing feature portfolio.
Latest Publications & Research Activity
Hey, Senior PMs: Shipping Faster Won’t Get You Promoted
The 3 Financial Metrics Every PM Needs on Their Scorecard
Frequently Asked Questions
Q:Is the PDI just a re-brand of technical debt?
No. Technical debt measures code quality; the PDI measures the financial carrying cost and enterprise valuation drag of that debt.
Q:How do you calculate the score?
The calculation involves weighing the ratio of maintenance engineering hours against new feature development, multiplied by the blended hourly cost of the engineering organization, normalized on a 0-100 scale.
Inspectable Evidence Ledger
Classified evidence items supporting, extending, or refining this canonical research specification.
| Evidence Item | Publisher | Evidence Type | Strength | Role | Action |
|---|---|---|---|---|---|
| Hey, Senior PMs: Shipping Faster Won't Get You Promoted | CIO.com | Tier-1 Article | ★★★★★ | Origin | Inspect ↗ |
| The 3 Financial Metrics Every PM Needs on Their Scorecard | Mind the Product | Industry Article | ★★★★ | Extends | Inspect ↗ |
| The Subprime Code Crisis | Beehiiv | Newsletter | ★★★★ | Extends | Inspect ↗ |
Recommended Citation
Ewing, R. (2026). "Product Debt Index (PDI)." Richard Ewing Research Canon. Available at: https://www.richardewing.io/concepts/product-debt-index
@article{ewing_product_debt_index,
author = {Ewing, Richard},
title = {Product Debt Index (PDI)},
journal = {Richard Ewing Research Canon},
year = {2026},
url = {https://www.richardewing.io/concepts/product-debt-index}
}