Methodology

Defaults are auditable. Sources are cited inline. Math is client-side and reproducible.

Oliver Wakefield-Smith

Founder, Digital Signet. Built siemcost / monitoringcost / itbudgetcalculator.

Updated 21 Jun 2026

Direct answer

This calculator computes CFR as failed_deploys / total_deploys over a rolling 7, 30, or 90 day window, with optional DORA-aligned exclusions for fix-only deploys and externally caused failures DORA Four Keys2024. Percentile mapping is interpolated from the 2024 DORA distribution chart DORA 2024 Report2024. Defaults are noted below; everything is overridable.

The CFR formula

CFR % = (failed_deploys / total_deploys) × 100, applied over the selected rolling window. With exclusions enabled, total_deploys is reduced by the fix-only-share fraction and failed_deploys is reduced by the externally-caused-share fraction. The default fix-only share is 12% and the default external share is 18%; both are operator-of-the-art defaults consistent with public DORA tooling integration patterns.

Percentile-band derivation

DORA does not publish raw decile tables. The percentile mapping (10/25/50/75/90 percentile anchors) is interpolated from the published 2024 DORA distribution chartDORA 20242024. Anchor values used: 0% → 100th, 1% → 90th, 2% → 83rd, 5% → 70th, 10% → 50th, 15% → 35th, 20% → 22nd, 30% → 10th, 45% → 3rd. Linear interpolation between anchors. This is the most honest reproducible mapping available from public data; correction welcome if DORA publishes raw deciles.

Engineering-burn assumptions

Annual burn = annual_failures × MTTR_hours × responder_count × hourly_rate. Responder count is capped at 8 (realistic median for structured incident response). Hourly rate is annual blended FTE cost / 2080. Default blended FTE cost is $180,000, a defensible US Series-C anchor.

Customer-impact churn assumption

The default $7,500-per-customer-facing-failure mid-anchor triangulates from IBM Cost of a Data Breach 2025 global average ($4.44M) IBM Cost of a Data Breach 20252025, SaaS single-incident churn risk (1-3% per affected customer over 90 days), and Series-C ACV clusters ($30K-$120K). Override for your account-base shape; for example, prosumer SaaS with $200 ACVs should set the per-failure number much lower.

Vendor-payback assumptions

The vendor-payback overlay assumes a 40% CFR reduction (the published Sleuth median improvement, scaled to be conservative). Per-seat rates are sourced from each vendor's public pricing page Sleuth Pricing2026 LinearB Pricing2026 Swarmia Pricing2026. Quote-only vendors (Jellyfish, Faros, DX, Haystack, Appfire Pluralsight Flow) do not display a per-seat rate; we never infer one.

What is sourced and what is calculated

All numeric DORA claims are sourced via CiteChip pills to either the 2024 DORA report (canonical source) or DORA's guides page (definitional source). All vendor pricing is sourced to the vendor's own pricing page with a verified-date stamp. Calculator outputs are derived from user inputs using the formulae above; nothing is server-side.