SLA calculator: first response due time in business hours
Most support SLAs only count business hours, which makes due times awkward to work out by hand across evenings and weekends. Enter when the ticket arrived, the target, and your hours.
Due by
Monday, Oct 12, 2026, 12:00 PM
A 4 hours target in business hours on a ticket received Friday, Oct 9, 2026, 4:00 PM ends 2 days 20 hours later on the clock.
Times are in whatever time zone you enter them in. Holidays aren’t counted; if one falls inside the window, add a day. Most help desks also pause the clock while a ticket waits on the customer.
SLA attainment
96.3%
More misses before you drop below 95%
6
462 of 480 tickets met the target. You can miss 6 more this period and still be at or above 95%.
Questions
How are business-hours SLAs calculated?
The clock only runs while the team is working. Start from the moment the ticket arrives (or the next opening time, if it arrives after hours), count down the target through each working day's open hours, and skip closed hours, weekends and holidays. A 4-hour target on a ticket received Friday at 4pm, with 9-to-5 hours on weekdays, is due Monday at noon.
What's a good first response time SLA?
One you can meet on almost every ticket with the team you have. Customers expect faster replies on live chat than on email, and urgent issues faster than questions. Set different targets by channel and priority, check your current response times first, and use the staffing calculator to see what a tighter target would cost in agents.
What is SLA attainment?
The share of tickets that met their SLA target in a period. If 480 tickets came in and 18 missed, attainment is 96.25%.
Should the SLA clock pause when we're waiting on the customer?
Usually, yes. Most help desks pause resolution-time SLAs while a ticket is pending on the customer, because the team can't move it forward. First response SLAs don't pause, since nobody has replied yet.
Link to this page
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<a href="https://flatdeskfinal.vercel.app/free-tools/sla-calculator">SLA due time calculator</a>Guides that go with this tool
- First response time: how to measure it, set a target and improve itWhat first response time is, how to calculate it in business hours, how to set a target you can keep, and the changes that bring it down without hiring.
- How to set up a support SLA your team can actually meetHow to choose first reply and resolution targets, handle business hours and pending tickets, and report attainment honestly.
- Support SLA templates: three starting points you can copy and adjustThree plain-language SLA templates for small teams: email only, chat and email, and priority customers. Each is a starting point, not one to copy blindly.
- Write an SLA customers can read: plain-language response promisesHow to turn your internal response targets into a short customer-facing SLA in plain language, with business hours, exclusions and what happens when you miss.
- Support for a SaaS selling to enterprisesHow to support enterprise buyers: answer security questionnaires, name contacts, agree escalation paths and keep large accounts informed.
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