Percentage of Legacy Resource
Definition
Measure of the percentage of resources running on ‘modern’ types (e.g. instance types, volume type). In general, cloud service providers come out with modern resource types that often come with improved price/performance. NOTE: Always compare the actual cost impact of a migration vs. level of effort required. Not all modernizations will result in cost savings. Always consider your active reservations before migrating workloads.
Formula, as published
Number of instances on ‘legacy’ resource types / total number of instances (can be done by app, account, total)
- Data sources:
- Cloud Console
Calculate it
Example values to start with; replace them with yours.
From the FinOps Foundation
More Usage Optimization KPIs
Definition and formula: Percentage of Legacy Resource, FinOps KPI library, FinOps Foundation, licensed CC BY 4.0, read 16 Oct 2026. Changed: HTML removed, dashes and British spellings changed, formula split from its data sources and examples. The calculator and the notes are Finitizer’s.
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