--- title: "MTTR Calculator" description: "MTTR calculator: work out mean time to restoration for one asset from its failures and the hours each took to get back in service." --- 1. [Home](/) 2. [Tools](/tools/) # MTTR calculator Work out mean time to restoration for one asset from its failures and the hours each took to get back in service. [Start free](https://app.fixahead.com/signup) - Free plan, no card. Example only. The starting values are invented: the pump in the worked example below. Mean time to restoration 8 hours Mean time to restoration 8 hours The average hours from a breakdown until the asset is back in service. [Start free](https://app.fixahead.com/signup) - [Enter your own figures](#figures) - [How the figure is worked out](#how-the-figure-is-worked-out) - [A worked example, step by step](#a-worked-example-step-by-step) ## Enter your own figures - **Failures restored.** Enter 0 or more. The number of breakdowns repaired in the period. Do not count preventive or planned jobs. - **Restoration hours.** Enter 0 or more. The hours from each breakdown until the asset was back in service, added together. Restoration hours are not labor hours: enter elapsed hours. Two technicians on one 3-hour job make 3 hours, not 6. Enter hours; 90 minutes is 1.5. Enter one asset's figures. Pooling assets of different types gives a figure for none of them. ## How the figure is worked out **MTTR (mean time to restoration)** is the expected time from a failure, or from its detection when the failure moment is unknown, until the asset is back in service. The figure is the average over an asset’s breakdowns. A lower figure means assets get back into service sooner. MTTR = R ÷ N - **R** is restoration hours. - **N** is the number of failures restored in the period. R includes the hands-on work and the waiting for people, parts, approvals and access. Hands-on time alone is a different, smaller measure: mean repair time. It is not MTTR. The [MTBF and MTTR guide](/blog/how-to-calculate-mtbf-mttr/) works through the method with a pump. [Maintenance metrics and KPIs](/guides/maintenance-metrics-and-kpis/) sets out when the restoration time starts. ## A worked example, step by step - Failures restored: 5 - Restoration hours: 40, the pump’s unplanned downtime, which included 14 hours of waiting for parts MTTR = 40 ÷ 5 = **8 hours** Of those 40 hours, 26 were hands-on repair. Hands-on time alone is mean repair time: 26 ÷ 5 = 5.2 hours.