SLA Deadline Calculator

Calculate an exact SLA (service level agreement) deadline from a start time and a required response window.

Service level agreements typically promise a response within some fixed window — "we'll respond within 4 hours" or "within 2 business days" — and calculating the actual deadline that promise implies requires the same kind of careful arithmetic as any duration calculation, complicated further by the fact that SLA windows are sometimes measured in straight clock hours and sometimes in business days specifically, which produce very different actual deadlines for the same numeric value.

Getting that deadline wrong in either direction has real consequences: understating it risks looking like you missed a commitment you actually met, while overstating it means missing a deadline you'd promised to hit — which is exactly why this calculation benefits from being done precisely rather than estimated, particularly for time-sensitive commitments where the exact hour matters.

This tool calculates the deadline directly from a start date and time plus a response window, letting you choose whether that window is measured in hours or business days — hours mode adds straight clock time including overnight rollover, while business-days mode correctly skips weekends — producing the exact deadline a support or operations team would need to track against.

1. Enter the start date and time.
2. Enter the response window and choose hours or business days.
3. Press Calculate to see the exact deadline.