The most complete online time duration calculator — calculate time duration between two times, add or subtract hours, convert time to decimal, track laps, and check world clocks in one place. Whether you need to find the elapsed time calculator for work shifts, flight schedules, or project deadlines, this free tool handles every time calculation instantly.
Our calculator is built on proven time arithmetic logic that correctly handles edge cases most tools miss — overnight shifts, leap years, daylight saving time boundaries, and month-length differences. Every result is validated to ensure the output you see matches real-world time calculations.
All calculations run entirely in your browser — there are no server calls, no account creation, and no waiting. Enter your times and click Calculate. The result appears in milliseconds. This online time duration calculator is available 24/7, works offline after the page loads, and is optimised for both desktop and mobile use.
Instead of visiting multiple sites to calculate time duration, add hours to a date, convert decimal time, and track laps, you get all eight calculators in one page. From the elapsed time calculator to the world clock, everything you need for time-related calculations is here — no tab-switching required.
We do not collect, store, or transmit any of the time data you enter. Your shift times, dates, and calculation results stay entirely on your own device. There are no cookies tracking your inputs, no data sold to third parties, and no analytics attached to individual calculations. What you calculate is your business — not ours.
A time duration calculator is an online tool that computes the exact amount of time between two points — be it seconds, minutes, hours, days, or even years. Unlike a standard calculator, it understands how time arithmetic works: 90 minutes becomes 1 hour 30 minutes, midnight crossovers are handled automatically, and AM/PM conversions are built in.
People use a time difference calculator every day for tasks that matter at work and in personal life. Payroll managers need to calculate time duration for employee timesheets. Nurses and doctors track elapsed time between medication doses. Project managers measure time duration between two dates to hit deadlines. Athletes and coaches log split times using a stopwatch and convert them for analysis. Pilots and travellers calculate flight durations across time zones.
What makes this tool different from a basic subtraction is the ability to handle the non-decimal nature of time — a system based on 60 seconds, 60 minutes, 24 hours, and 365 days. Our online time duration calculator manages all of that complexity so you get an accurate result in one click.
| Unit | Equivalent |
|---|---|
| 1 minute | 60 seconds |
| 1 hour | 60 minutes / 3,600 seconds |
| 1 day | 24 hours / 1,440 minutes |
| 1 week | 7 days / 168 hours |
| 1 month (avg) | 30.44 days / 730.5 hours |
| 1 year | 365.25 days / 8,766 hours |
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 min | 0.08 | 35 min | 0.58 |
| 10 min | 0.17 | 40 min | 0.67 |
| 15 min | 0.25 | 45 min | 0.75 |
| 20 min | 0.33 | 50 min | 0.83 |
| 25 min | 0.42 | 55 min | 0.92 |
| 30 min | 0.50 | 60 min | 1.00 |
Convert standard time to decimal hours for easier calculations.
Extract minutes from the decimal portion.
Calculate the difference between two times.
Calculate days between two dates using milliseconds.
Pick the tool that fits your need. Use the Time Duration Calculator to find how many hours between two times. Use Add / Subtract Time to shift a start time forward or backward. Use Date Duration Calculator to get the time duration between two dates in days, weeks, and months. Each calculator works independently — no setup needed.
Type in your start time and end time using hours and minutes. The tool accepts both 12-hour (AM/PM) and 24-hour formats. For date-based calculations, use the date picker. For the work hours calculator, enter your shift start and end — overnight shifts crossing midnight are handled automatically.
Choose whether to Add or Subtract time, select AM or PM if using 12-hour format, and decide whether to include the end date in a date range count. Once ready, click Calculate. Your result appears instantly — broken down into hours, minutes, and seconds so there is no ambiguity.
Copy your result directly into a timesheet, payroll system, schedule, or report. Need the duration in decimal form for payroll software? Switch to the Time to Decimal converter — 7 hours 45 minutes becomes 7.75 in one click. Need to convert the other way? Use Decimal to Time to get back a human-readable format.
The most common reason people use a work hours calculator is to track shifts for payroll. Enter your shift start (e.g. 9:00 AM) and end time (e.g. 5:30 PM), subtract a 30-minute break, and get exact billable hours. Our calculator handles overnight shifts — a 10:00 PM to 6:30 AM night shift correctly returns 8 hours 30 minutes, not a negative number. Once you have your total billable hours, use our Loan Calculator to plan salary-based repayments or financial commitments.
Travellers use a time difference calculator to work out how long a journey takes. Enter your departure and arrival time to instantly calculate your flight duration. This is especially useful for long-haul flights where arrival is the next day. Combined with the World Clock section, you can also figure out what local time it is when you land in a different time zone.
Athletes and coaches use the built-in stopwatch and elapsed time tools to record race splits, track training intervals, and analyse performance. The elapsed time calculator is also used in sports officiating — to record injury time, timeouts, and match duration. Lap times are logged individually and can be exported for review after a session. Athletes tracking training duration may also find our Calorie Calculator useful for estimating energy burned during timed workout sessions.
Use the time duration between two dates feature to calculate how many days remain until a deadline, how long a project phase took, or when a contract expires. Project managers enter a start date and add working days to find the exact completion date. This is far more reliable than counting manually on a calendar — especially across months with different lengths.
Medical professionals rely on precise time tracking. Nurses use an online time duration calculator to track how many hours since a patient’s last medication, how long a procedure took, or how much time has passed since symptom onset. In neonatal care, NICU staff calculate the exact age of a premature baby in weeks and days using the date duration tool.
Teachers use the duration calculator to plan lesson segments and exam scheduling. Students use it to manage study time — breaking a 3-hour revision block into focused 25-minute Pomodoro sessions. The stopwatch feature is ideal for timed mock exams. Schools also use the date calculator to determine the number of school days remaining in a term or academic year. Students tracking exam performance alongside study time can also use our Grade Calculator to monitor their academic progress.
Our time duration calculator is built for anyone who works with time professionally or personally. Here are the groups that rely on it most:
Regardless of your profession, the ability to calculate time duration accurately saves you from manual errors, disputes over hours, and missed deadlines. This tool is free, requires no login, and works on any device.
To calculate time duration between two times, enter your start time and end time into the Time Duration Calculator above and click Calculate Duration. The result shows the exact hours, minutes, and seconds between the two times. For example, from 9:00 AM to 5:45 PM is 8 hours and 45 minutes. Our time duration calculator handles both 12-hour and 24-hour formats and automatically resolves overnight crossings (e.g. 10:00 PM to 6:00 AM = 8 hours).
Use the Time Duration Calculator section on this page. Enter your start time (e.g. 08:30) and end time (e.g. 17:00), then click Calculate Duration. The tool will show you exactly how many hours between two times — in this case, 8 hours 30 minutes. You can also switch the result to decimal form (8.5 hours) using the Time to Decimal converter, which is useful for payroll and billing purposes.
As a work hours calculator, enter your clock-in time as the Start Time and your clock-out time as the End Time. Click Calculate Duration to get your total hours worked. If you have a break, use the Add/Subtract Time calculator to subtract the break duration from your total. For multiple days, repeat the process for each shift and add the totals together. Convert your final result to decimal using the Time to Decimal tool for payroll systems that require decimal hours (e.g. 7:30 = 7.5).
Both terms describe the same core function — finding the gap between two times. A time difference calculator typically focuses on the interval between a start and end point, while a time duration calculator may also include tools to add or subtract time, convert between formats, and calculate durations spanning multiple days or dates. Our tool covers all of these use cases in one place, making it a comprehensive solution for any time-related calculation.
To use this as an elapsed time calculator, enter the time an event started as your Start Time and the current time (or end time) as your End Time, then click Calculate Duration. The result is the elapsed time — how much time has passed. For real-time elapsed tracking, use the built-in Stopwatch, which measures elapsed time down to milliseconds and supports lap recording. This is useful in medical settings, sports, and quality control processes where precise elapsed time matters.
To find the time duration between two dates, use the Date Duration Calculator section. Select your start date and end date using the date picker and click Calculate Duration. The result shows the total number of days, and also breaks it down into years, months, and days for readability. You can also choose to include or exclude the end date in the count — useful when calculating contract lengths, age, or subscription periods where the last day counts.
Divide the minutes by 60 and add that number to the hours. For example, 2 hours 30 minutes = 2 + (30 ÷ 60) = 2.5 decimal hours. Use the Time to Decimal section above for instant conversion — enter your hours, minutes, and seconds and click Convert to Decimal. This format is required by most payroll software including QuickBooks, Xero, and ADP. To reverse the process, use Decimal to Time (e.g. 7.75 hours = 7 hours 45 minutes).
Yes. The online time duration calculator is designed to handle shifts that cross midnight automatically. If your start time is later than your end time (e.g. start 22:00, end 06:00), the calculator correctly interprets this as a next-day end time and returns 8 hours. This is one of the most common sources of error in manual timesheet calculations — and this tool eliminates it completely.
Yes, this time duration calculator is completely free to use with no registration or account required. It works on all devices — desktop, tablet, and mobile. All calculations happen instantly in your browser, so your data is never sent to a server. There are no limits on how many calculations you can run, and no premium features locked behind a paywall.
Use the World Clock section at the bottom of the page to see current times across major cities — New York, London, Paris, Dubai, Tokyo, and Sydney. Time zones are expressed as UTC offsets: EST is UTC-5, IST is UTC+5:30, GMT is UTC+0. To convert a time from one zone to another, note the UTC offset difference and use the Add/Subtract Time tool to apply it. For example, converting 3:00 PM EST to IST: add 10 hours 30 minutes to get 1:30 AM IST (next day).