Bug Fix Cost Calculator
Work out what fixing a set of defects costs to fix, retest and release.
In short
Work out what fixing a set of defects costs to fix, retest and release.
Formula: Hours = Defects × (Hours to fix one + Retest hours per defect); Cost = Hours × Loaded cost per hour + Release and deployment cost
What this calculator does
Internal failure cost as defined by the cost-of-quality model: effort spent correcting defects, valued at the organisation's own loaded rate. Defect counts and fix times are the organisation's own measurements.
Use it to turn Currency, Defects to fix, Hours to diagnose and fix one defect, Loaded cost per engineer hour, and the other shown inputs into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this professional & industry calculation.
Inputs and what they mean
- Currency
- — Amounts are shown in the currency you pick. No exchange rate is applied..
- Defects to fix
- — number value.
- Hours to diagnose and fix one defect
- — Your own recorded average..
- Loaded cost per engineer hour
- — number value.
- Retest and review hours per defect (optional)
- — Optional component. Leave at 0 to exclude it from the result..
- Release and deployment cost (optional)
- — Optional component. Leave at 0 to exclude it from the result..
How to use it
- Enter your own figures — the calculator never fills in a rate, price or benchmark for you.
- Press Calculate to see the result.
- Read the formula, variables, assumptions and source below the result before you rely on it.
Formula
Hours = Defects × (Hours to fix one + Retest hours per defect); Cost = Hours × Loaded cost per hour + Release and deployment cost.
Inputs used: Currency, Defects to fix, Hours to diagnose and fix one defect, Loaded cost per engineer hour, Retest and review hours per defect (optional), Release and deployment cost (optional).
Edge handling: Defects to fix is required.; Defects to fix cannot be negative.; Defects to fix must be no more than 1000000000.; Hours to diagnose and fix one defect is required.; Hours to diagnose and fix one defect cannot be negative..
Worked example
120 defects at 5.5 hours each
- Start with Currency: USD, Defects to fix: 120, Hours to diagnose and fix one defect: 5.5, Loaded cost per engineer hour: 85, Retest and review hours per defect (optional): 1.5, Release and deployment cost (optional): 2500.
- Apply the method: Hours = Defects × (Hours to fix one + Retest hours per defect); Cost = Hours × Loaded cost per hour + Release and deployment cost.
- An internal failure cost built from your own defect data.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Inputs outside the supported range are rejected rather than forced into a result.
- The result depends on the values you enter for this bug fix cost calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Reference: American Society for Quality — Cost of quality — prevention, appraisal and failure costs
Last reviewed:
Common questions
Where does this formula come from?
ASQ, Cost of Quality — internal failure cost is the labour and rework spent correcting defects found before delivery. See the source link on this page.
What kind of calculation is this?
Internal failure cost: the labour spent correcting defects, plus any release cost the correction triggers. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.
What are its limits?
Counts correction cost only; it does not value the impact of the defects on customers. An average over the defects in scope, not a per-defect estimate.
How do I use the Bug Fix Cost Calculator?
Enter the required values for Currency, Defects to fix, Hours to diagnose and fix one defect, Loaded cost per engineer hour, Retest and review hours per defect (optional), and the other fields shown. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the Bug Fix Cost Calculator use?
Hours = Defects × (Hours to fix one + Retest hours per defect); Cost = Hours × Loaded cost per hour + Release and deployment cost The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.
Can the Bug Fix Cost Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
Formula, source and verification
Internal failure cost: the labour spent correcting defects, plus any release cost the correction triggers.
The question it answers: What will it cost us to clear these defects?
The formula
Hours = Defects × (Hours to fix one + Retest hours per defect); Cost = Hours × Loaded cost per hour + Release and deployment cost
- D — Defects to fix
- (defects). Number of defects in scope.
- h — Hours to diagnose and fix one defect
- (h). The organisation's own recorded average.
- t — Retest and review hours per defect
- (h). Optional appraisal effort per defect.
- r — Loaded cost per engineer hour
- (currency/h). Employer cost per engineer hour.
- R — Release and deployment cost
- (currency). Optional cost of shipping the corrections.
Units: Defects; hours; currency.
What kind of calculation this is
Deterministic formula. The same inputs always give the same answer. The maths is fixed and does not depend on judgement.
Method
Internal failure cost as defined by the cost-of-quality model: effort spent correcting defects, valued at the organisation's own loaded rate. Defect counts and fix times are the organisation's own measurements.
Assumptions built into the result
- Mathematical: The hours per fix are an average over the defects in scope.
Figures this calculator will never guess for you
- No industry delivery rate, productivity figure, defect rate or cost per line is inserted.
- No optional component is filled in on the user's behalf.
- No cost-of-defect multiplier by development phase is applied.
Limitations
- Counts correction cost only; it does not value the impact of the defects on customers.
- An average over the defects in scope, not a per-defect estimate.
Source and version
- Standard or reference
- Cost of quality — internal failure cost — American Society for Quality (ASQ, Cost of Quality — internal failure cost is the labour and rework spent correcting defects found before delivery.)
- Published source
- American Society for Quality — Quality resources
- Formula version
- Version 1
- Verification
- Reviewed against the cited source on
- How much weight the source carries
- Standards or government
- Applies to
- Currency
- Amounts stay in the currency you choose; no exchange rate is applied.
Cite this page
Free Calculator. (2026, September 16). Bug Fix Cost Calculator. https://freecalculator.tech/tools/bug-fix-cost-calculator
"Bug Fix Cost Calculator." Free Calculator, 16 Sept. 2026, https://freecalculator.tech/tools/bug-fix-cost-calculator.
Bug Fix Cost Calculator — Free Calculator, https://freecalculator.tech/tools/bug-fix-cost-calculator
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