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On-call coverage calculator
Estimate rotation load and available coverage when people take leave or are not yet ready for on-call.
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How this result is calculated
Required seat-hours = coverage hours × concurrent seats. Effective responder capacity = trained people × (1 − unavailable percentage). Dividing seat-hours by effective capacity estimates average scheduled availability per person; it is not active incident work. The minimum roster rounds required capacity up to a whole person.
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# On-call coverage calculator Tool defaults; replace with your settings before operational use. ## Review issues - Trained responders: enter a whole number from 1 to 10000. - Concurrent seats cannot exceed trained responders. ## Inputs Team and coverage scope: Not entered Hours covered per week: 168 Concurrent responder seats: 2 Trained responders: Not entered Unavailable capacity (%): 15 Maximum coverage hours per person per week: 42 Shift length (hours): 12 ## Method Required seat-hours = coverage hours × concurrent seats. Effective responder capacity = trained people × (1 − unavailable percentage). Dividing seat-hours by effective capacity estimates average scheduled availability per person; it is not active incident work. The minimum roster rounds required capacity up to a whole person. This is a capacity estimate, not a roster generator. It does not resolve time-zone overlap, holidays, consecutive shifts, skill mix or local employment requirements. The two seats are assumed interchangeable across all trained responders. https://aiopssre.com/on-call-coverage-calculator/
How it works
Required seat-hours = coverage hours × concurrent seats. Effective responder capacity = trained people × (1 − unavailable percentage). Dividing seat-hours by effective capacity estimates average scheduled availability per person; it is not active incident work. The minimum roster rounds required capacity up to a whole person.
Follow the example
Eight responders covering two continuous seats need 336 seat-hours each week. With 15% capacity unavailable, the effective roster is 6.8 people and the average load is 49.41 hours. A 42-hour limit requires ten trained people under these assumptions.
What to account for
This is a capacity estimate, not a roster generator. It does not resolve time-zone overlap, holidays, consecutive shifts, skill mix or local employment requirements. The two seats are assumed interchangeable across all trained responders.