--- title: "MTTR: what it is and how to calculate it | attendo" description: "What MTTR (mean time to repair) is, how to calculate it, why it matters where the clock starts and the mistake of using it to judge technicians." url: "https://attendo.me/en/glossary/mttr" lang: "en" --- # MTTR: what it is and how to calculate it Also known as: Mean time to repair MTTR (mean time to repair) is the average time it takes to bring equipment back into service after it fails. It measures responsiveness, not reliability. How to calculate it MTTR = total repair time ÷ number of repairs ## Where the clock starts It is the decision that changes the result the most, and it is rarely made. When the equipment fails? When someone reports it? When the technician arrives? An MTTR of 2 hours and one of 9 can describe the same service with a different starting point. The honest approach is to measure the whole time, from failure to restart, and **break it down**: detection, travel, waiting for parts and repair. That is where the real problem shows up, and it is often waiting for materials rather than working time. ## MTTR and MTBF [MTBF](https://attendo.me/en/glossary/mtbf) tells you how often equipment fails; MTTR, how long it takes to come back. Together they give you [availability](https://attendo.me/en/glossary/availability). ## And MTTA MTTA (mean time to acknowledge) measures what happens before the repair: from the moment a request comes in until someone picks it up. If both MTTR and MTTA are high, the problem is not the repair but how requests come in and get assigned. ## The usual mistake Using MTTR to measure technicians. If most of the time is spent waiting for parts, what needs fixing is the storeroom, not the pace of work. Review your [critical spare parts](https://attendo.me/en/glossary/critical-spare-part) before you look at people. ## In attendo [attendo CMMS](https://attendo.me/en/cmms) calculates MTTR on closed work orders, next to MTBF and MTTA. Each work order stores the type and length of the equipment downtime, and the [app](https://attendo.me/en/modules/mobile-app) timer tracks working hours. - [attendo CMMS](https://attendo.me/en/cmms) ## Where it is used in attendo ### Modules - [Assets and inventory](https://attendo.me/en/modules/assets): Each asset with its own record, QR code, history and readings - [Warehouse, purchasing and stock](https://attendo.me/en/modules/purchasing-and-stock): Warehouses, stock, purchasing and suppliers, without a spreadsheet - [Mobile app and Field Radar](https://attendo.me/en/modules/mobile-app): The service report on your phone, offline, and a map of who can go - [Reports and dashboards](https://attendo.me/en/modules/reports-and-dashboards): Reports and dashboards for every area, with today’s data ### Industries that use these modules - [IT services and MSPs](https://attendo.me/en/industries/it-services) - [Energy and renewables](https://attendo.me/en/industries/energy-renewables) - [Testing, inspection and laboratories](https://attendo.me/en/industries/testing-inspection) - [Facility maintenance and services](https://attendo.me/en/industries/facility-maintenance) - [And any other business](https://attendo.me/en/industries) ## Related terms Maintenance ### MTBF Mean time between failures MTBF (mean time between failures) is the average time a piece of equipment runs properly between one breakdown and the next. It measures reliability. Maintenance ### Availability Asset availability Availability is the percentage of time an asset is in a condition to operate. Maintenance ### Critical spare part Critical spare A critical spare part is one whose absence holds up the repair and drags out the equipment’s downtime. It is not the most expensive part or the most used one: it is the one you cannot get quickly. ### On the blog #### How to calculate MTBF and MTTR without fooling yourself Both formulas fit on one line. The hard part is making the number mean something. Here are the formulas, a complete example and the three mistakes that turn these KPIs into decoration. 4 min read [See all 53 glossary terms](https://attendo.me/en/glossary) ## Shall we look at it with your data? We will show you how what you just read works in attendo, with your own assets, tickets and customers. If it is not a fit, we will tell you. - With your operation, not a generic demo - A real person from our team replies - No cold calls afterwards Would you rather talk first? - Phone [+34 910 053 530](tel:+34910053530) - Email [sales@attendo.me](mailto:sales@attendo.me) - Monday to Thursday 9:30 AM to 6:30 PM and Friday 9:30 AM to 2:30 PM (Spain time)