The Time Duration Calculator tells you exactly how much time falls between a start time and an end time. It handles same-day intervals as well as spans that cross midnight into the next day, making it useful for shift work, event timing, travel planning, study sessions, and any situation where you need a precise time gap. Choose from multiple output formats and optionally include seconds for extra precision.

How to Use the Time Duration Calculator

Follow these steps to calculate your time interval:

1. Enter your start time — Select the hour, minutes, and AM/PM. If you need second-level precision, enable “Include Seconds” first to reveal the seconds input.
2. Enter your end time — Select the hour, minutes, and AM/PM for when the interval ends. Add seconds if enabled.
3. Include dates (optional) — Toggle “Include Dates” to enter start and end dates when your interval spans across midnight into the following day, such as a night shift running from 10:00 PM to 6:00 AM.
4. Include seconds (optional) — Enable this toggle to add second inputs to both time fields and include seconds in the output.
5. Select your output format — Choose how you want the result displayed: hours and minutes, total minutes only, decimal hours, or a full breakdown of days, hours, minutes, and seconds.
6. Calculate — Click “Calculate Duration” to instantly generate your result.
7. Review your result — The duration is displayed in a clear summary card with a plain-language description alongside the formatted output you selected.
8. Reset — Click “Reset” to clear all fields and start a new calculation.

Why Use This Calculator?

Multiple output formats — View your result as hours and minutes, total minutes, decimal hours, or a full days-hours-minutes-seconds breakdown. Pick the format that suits your needs, whether you are filling in a timesheet, calculating billable hours, or logging an event.

Cross-midnight support — Enable the date fields to accurately calculate intervals that run past midnight. The calculator correctly handles overnight spans without you needing to do any manual adjustment.

Optional seconds — For situations where precision matters, toggle on seconds to include them in both the input and the output.

Instant results — Your duration appears immediately with no page reload. A clean summary card displays the result alongside a plain-language explanation of the interval.

Free and accessible — Works in any browser on any device with no account, download, or payment required.