Technical and media time

System Uptime and Downtime Calculator

Calculate availability, downtime budget, incident frequency, and MTTR.

PrivacyRuns in your browser
OutputAnalytics dashboard
CostFree to use
Analytics dashboard

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Purpose and scope

What this dashboard measures

Calculate availability, downtime budget, incident frequency, and MTTR.

Measurement period (hours), Total downtime (minutes), Incidents, Availability target (%), and Average affected users feed the breakdown values beneath the System Uptime and Downtime Calculator headline; Save Average affected users in its entered unit for comparison.

InterfaceAnalytics dashboard
CategoryTechnical and media time
Review focusHeadline and units

Instructions

How to use this calculator

Enter the measurement period, downtime, incident count, availability target, and average affected users.

  1. Confirm Measurement period (hours) and Total downtime (minutes) from one System Uptime and Downtime Calculator reporting period.
  2. Confirm Incidents, Availability target (%), and Average affected users without changing the Average affected users unit.
  3. Create the System Uptime and Downtime Calculator and evaluate its headline with breakdown values.
  4. Isolate Average affected users in a second System Uptime and Downtime Calculator run to identify any boundary or rounding effect.

Interpretation

Interpreting the headline metric

Read measured availability, target budget, and MTTR together. A good percentage can still hide severe concentrated incidents.

Trace Measurement period (hours), Total downtime (minutes), and Incidents beside the System Uptime and Downtime Calculator headline; Average affected users reveals rounding across the breakdown values.

Calculation

Method used

Availability is successful operating time divided by total measured time. MTTR divides downtime by incidents and the target determines a downtime budget.

Availability = (period minutes − downtime minutes) ÷ period minutes × 100. MTTR = downtime ÷ incidents.

The System Uptime and Downtime Calculator evaluates Measurement period (hours), Total downtime (minutes), and Incidents separately; save Average affected users visible outside any percentage, rate, or total.

Calculation method last reviewed: June 21, 2026.

Worked scenario

Example calculation

Example: Ninety-five downtime minutes in a 720-hour month produces an availability percentage and can be compared with a 99.9-percent budget.

Evaluate Average affected users with the System Uptime and Downtime Calculator breakdown values before judging the Average affected users headline scale or units.

Visual audit

Reading the supporting metrics

The System Uptime and Downtime Calculator dashboard places breakdown values beside Measurement period (hours), Total downtime (minutes), Incidents, Availability target (%), and Average affected users. Trace Average affected users in its original unit before accepting the breakdown values or headline status.

Boundaries

Important edge cases and limitations

Partial degradation, regional weighting, planned maintenance, excluded events, and contractual calculation methods are not represented.

Replace Average affected users in the System Uptime and Downtime Calculator before reading the breakdown values or headline.

Input audit

Checklist for this calculation

  • Trace the System Uptime and Downtime Calculator period and Measurement period (hours) and Total downtime (minutes) units.
  • Evaluate Average affected users with the System Uptime and Downtime Calculator breakdown values.
  • Create a fresh System Uptime and Downtime Calculator after any Average affected users replace.
  • Save Incidents, Availability target (%), and Average affected users beside the System Uptime and Downtime Calculator; include Average affected users in any saved or shared record.

Practical use

Recommended workflow

Agree on the availability definition before collecting data, then track error budget consumption throughout the period.

Questions

Frequently asked questions

Is 99.9 percent the same for every measurement period?

The percentage is the same, but the allowed downtime changes with the length of the month, quarter, or year.

What changes when Average affected users is adjusted in the

Save Measurement period (hours) and Total downtime (minutes) unchanged and replace Average affected users once in the System Uptime and Downtime Calculator. Evaluate the Average affected users component with breakdown values to identify a proportional or threshold effect.

How does Average affected users qualify the system uptime and downtime calculator headline?

The System Uptime and Downtime Calculator headline compresses Measurement period (hours) and Total downtime (minutes), so evaluate it with Average affected users and breakdown values. The Average affected users denominator then exposes rounding in the System Uptime and Downtime Calculator.

What belongs in an audit note for the

Keep the System Uptime and Downtime Calculator headline beside Incidents, Availability target (%), and Average affected users, while Measurement period (hours) and Total downtime (minutes) identifies the run being compared. Add units and the calculation date.