Flaky test cost calculator
Flaky tests cost more than wasted CI minutes — they cost engineer hours spent triaging failures that were never real. Put in your own numbers below to see the monthly and annual bill in triage time alone. The defaults reproduce a documented mid-size-team scenario: about $6,100 a month, or $73,200 a year.
Your team
× 21 working days = 3,150 runs/month. Pull the real number from your CI dashboard.
Share of runs surfacing a flaky-suspected failure. Google ~1.5% to Bitrise 26% brackets a starting range.
Time to investigate one flaky-suspected failure. Default is Slack's measured ~28 minutes.
Not take-home pay. BLS median $133,080 ≈ $64/hr, plus 25–40% overhead ≈ $80–90.
Triage cost of flaky tests
| Flake rate | Hrs/mo | Cost/mo | Cost/yr |
|---|---|---|---|
| 1% | 15 | $1,220 | $14,641 |
| 5% | 74 | $6,101 | $73,206 |
| 10% | 147 | $12,201 | $146,412 |
Every default is sourced (see below), and the result updates live. Use the Copy shareable link button to send your exact scenario to a teammate — the numbers travel in the URL.
How the calculation works
The model is deliberately transparent — one line you can check by hand:
- CI runs per month. Runs per day × 21 working days. The default 150/day (≈ 3,150/month) is a mid-size team; pull your real number from your CI provider's dashboard.
- Flaky-failure rate. The share of runs surfacing a flaky-suspected failure. If you don't track it yet, Google's ~1.5% and Bitrise's 26% bracket a reasonable range; 5% is a common mid-size figure.
- Triage minutes per failure. Default is Slack's measured ~28 minutes — the most-cited public benchmark.
- Fully loaded engineer rate. Not take-home pay. The BLS median of $133,080/year is ≈ $64/hour; add 25–40% for benefits and overhead and you land around $80–90. The calculator defaults to $83.
This counts triage time only — the part that is easiest to defend with a number. It undercounts the real cost: the release sitting blocked during investigation, the ~25-minute context-switch tax of resuming interrupted work (toggle it on to include it), and the genuine regressions that get waved through as "probably flaky." The full breakdown is in the real cost of flaky tests.
Stop estimating — measure your real flaky-failure rate
Connect your CI and Qualflare scores every test's flakiness across runs, so the rate you plug in here becomes a number you can watch go down. Flaky test detection, free to start.
Get Started FreeFrequently asked questions
How much do flaky tests cost?
The triage cost of flaky tests is CI runs per month × your flaky-failure rate × triage minutes per failure ÷ 60 × fully loaded engineer hourly rate. As a worked example, a team running CI ~150 times a day (about 3,150 runs a month) with a flaky failure on 5% of runs, at Slack’s measured ~28 minutes of triage per failure and an $83/hour fully loaded rate, spends roughly 74 engineer-hours and about $6,100 a month — around $73,200 a year — on triage alone.
How is the flaky test cost calculated?
Multiply your monthly CI run volume by your flaky-failure rate to get flaky-suspected failures per month. Multiply that by triage minutes per failure and divide by 60 to get engineer-hours. Multiply by your fully loaded engineer hourly rate for the monthly cost, and by 12 for the annual cost.
What hourly rate should I use for engineering time?
Use a fully loaded rate, not base salary. The U.S. Bureau of Labor Statistics put the 2024 median U.S. software developer salary at $133,080/year — about $64/hour across a 2,080-hour work year. Add the industry-standard 25–40% for benefits, payroll taxes, and overhead and you land around $80–90/hour fully loaded. The calculator defaults to $83.
Does this calculator capture the full cost of flaky tests?
No — it deliberately counts only triage time, the part that is easiest to defend with a number. It undercounts the release that sits blocked while someone investigates, the ~25-minute context-switch tax of resuming interrupted work (which you can toggle on), and the real regressions waved through as “probably flaky.” Treat the result as a conservative floor, not a ceiling.
Related: flaky test detection · the real cost of flaky tests · flaky test statistics · complete guide to flaky tests
Sources
- U.S. Bureau of Labor Statistics — Software Developers (median $133,080/yr, May 2024)
- Mark, Gonzalez & Harris — "No Task Left Behind? Examining the Nature of Fragmented Work" (CHI 2005)
- Runway — Fully Burdened Labor Rate (25–40% overhead benchmark)
- Qualflare — Flaky test statistics (Slack ~28-min triage benchmark, compiled)
Built by İbrahim Süren, founder of Qualflare. Model published August 2026.