Tech debt costs $33K to $55K per engineer per year, before incidents and compounding.
Stripe measured engineers spending about a third of the week on technical debt: 13.5 of 41 hours, rising to 17.3 hours once all maintenance is counted. At median US salaries that is roughly the cost of a junior engineer per senior engineer, every year. This page gives you the answer in 60 seconds. The calculator and the research live next door.
Core Sample 01
The 60-second summary
Five facts your VP of Engineering needs in their pocket. Each layer is a finding from a named study. Read top to bottom: most recent at the surface, oldest data deepest.
Layer 01 / Surface / Deloitte 2026
21 to 40% of IT spending goes to servicing technical debt; older organisations skew higher.
Layer 02 / McKinsey 2020-23
20 to 40% of the technology estate's value is tech debt; 10-20% of the new-product budget is diverted to servicing it.
Layer 03 / CAST 2025
Global technical debt totals 61 billion days of repair time across 10B+ lines of code analysed.
Layer 04 / CISQ 2022
Total US poor-software-quality cost: $2.41 trillion, of which $1.52T is debt.
Layer 05 / Stripe 2018 / Bedrock
17.3 hours per week per engineer lost to maintenance and bad code (33%).
Reference Card 01
Per-developer cost: pick your row
Annual debt cost per engineer at common fully-loaded salary levels and drag rates. Screenshot this for the budget meeting.
cost = salary x drag_pct. Fully-loaded = base + benefits + overhead (~1.4x base). Industry midpoint: 30% drag.
Compound Strata
The deeper you dig, the more you find.
Untouched debt accrues 15-25% per year. Workarounds layer on workarounds. The data model that was right for 10K users blocks the migration to 10M. A 10-person team starting at $390K of drag finds itself paying $1.05M five years on.
See budgetoverrun.com for the broader picture on engineering budget overruns.
10-person team, $130K fully-loaded, 30% starting drag, 18% annual compound (modeling-convention midpoint).
Decision Layer
What to do next
Pick the page that matches your immediate need. Each is a 2-minute read.
Measure your number
Four methods in 5 minutes. Survey, static analysis, cycle time, post-mortems. Pick one to start.
Pitch leadership
Translation table, five-slide structure, top objections answered. The one-pager for your VP meeting.
Reduce the burden
Three sprint allocation models, prioritisation tiers, prevention checklist. Cheat sheet format.
Calculate ROI
Payback inside a year, ~80-200% year-one ROI in our scenarios. Three sizes. When not to invest. The yes-or-no answer.
Need the interactive calculator? techdebtcalculator.com has the full ROI modeller, scorecards, and PDF export. Need the deep research? technicaldebtcost.com has the full studies, by-industry breakdowns, and attrition data. This site is the cheat sheet that links to both.
git blame --reverse
Where the cost shows up
The five line-items the CFO will recognise. Each one is the same debt, billed against a different account.
Field Notes
Frequently asked, quickly answered
How much does tech debt cost per developer?+
$33,000 to $55,000 per engineer per year, roughly a third of fully-loaded salary. At a $160K fully-loaded cost with 33% drag (Stripe 2018) that is $52,800 per engineer per year.
What percentage of engineering time goes to tech debt?+
About a third, per Stripe 2018: 13.5 of 41 hours a week on technical debt (33%), up to 17.3 hours (42%) on maintenance overall. Most organisations land in the 25-35% band.
Does technical debt get worse over time?+
Yes. Tech-debt cost models commonly assume 15-25% annual compounding on untouched debt, the interest-rate analogy popularised by Ward Cunningham and Steve McConnell. A $400K drag in year one becomes over $1M by year five. Workarounds layer on workarounds, dependencies drift, tribal knowledge evaporates.
How do you calculate tech debt cost?+
Simplest formula: annual_cost = team_size x fully_loaded_cost x drag_percentage. A 25-person team at $160K fully-loaded with 30% drag is $1.2M per year. For three formal methodologies (productivity-loss, SQALE, interest-accrual) and the interactive calculator, see techdebtcalculator.com.
Is tech debt worth fixing?+
Yes for targeted initiatives. Our scenarios show payback inside a year (3-18 months) and year-one ROI of roughly 80-200%, driven mostly by scope discipline. Skip it if the product is being sunset, the debt sits in rarely-touched code, or a full rewrite is already approved. See /roi for the decision framework.
How do you present tech debt cost to a CFO?+
Translate to dollars not code quality. Lead with annual payroll cost, show 5-year compound growth, propose a specific investment with payback period. Avoid the words 'refactoring' and 'code quality' in the room. See /pitch for the cheat sheet.
Stratum 06 / Exec Pitch Library
Briefings by stakeholder, by metric, by stage
Twenty bespoke briefings for the conversations that decide whether tech debt gets funded. Each is a one-page-style summary, board-pack-ready, with the dollar arithmetic in the right native unit for the audience.
Per business metric
Per company stage
Per financial framework
Decision