How do I add hours and minutes together?

Enter each duration in HH:MM:SS format and use the Add operation. The calculator totals the seconds, carries over to minutes (every 60 seconds), then to hours (every 60 minutes). Example: 2:45:30 + 1:30:45 = 4:16:15.

How do I calculate hours between two times?

Enter the start and end clock times in the Time Between mode. The calculator subtracts start from end and returns the elapsed duration. Example: 09:00 to 17:30 = 8 hours 30 minutes. If the end time is earlier than the start, it assumes the next day (overnight shift).

What is decimal time and how do I convert it?

Decimal time expresses hours as a single number with a fractional part instead of HH:MM. For example, 1 hour 45 minutes = 1.75 decimal hours (45 ÷ 60 = 0.75). This format is commonly used for timesheets, payroll, and billing because it simplifies multiplication by hourly rates.

How do I calculate net work hours after breaks?

Use the Work Time mode: enter your shift start, shift end, and total break minutes. Net hours = gross hours minus break time. Example: start 08:00, end 16:30, 30-min break → gross 8h 30m, net 8h 00m. You can also enter an hourly rate to see your estimated earnings.

How do I multiply or divide a time duration?

Enter a duration (e.g., 1:30:00) and a factor. Multiply calculates repeated durations: 1:30:00 × 3 = 4:30:00. Divide splits a duration evenly: 6:00:00 ÷ 4 = 1:30:00. This is useful for estimating total time for repeated tasks or splitting time across team members.

How do I sum multiple time entries for a timesheet?

Use the Sum Multiple mode to add labeled time rows. Enter each task or day with its duration, then the calculator totals all entries and shows the sum plus an average per entry. You can also export the entries as a CSV file for your records.

How do I convert minutes to hours or hours to days?

Use the Convert mode. Select the source unit and target unit, enter the value, and the calculator shows the result plus a full breakdown in all units. Example: 150 minutes = 2.5 hours = 0.1042 days. Supported units: seconds, minutes, hours, days, weeks, months, and years.

How does the overnight time calculation work?

When the end time is earlier than the start time, the calculator automatically assumes the shift crosses midnight. It adds 24 hours to the end time before subtracting. Example: start 22:00, end 06:00 → 8 hours (not negative 16 hours). An overnight indicator flag confirms this adjustment.

What time will it be in X hours from now?

Use the "In X Hours" mode. Enter a start time (e.g., 14:30) and a duration to add (e.g., 5 hours 45 minutes). The calculator returns the future clock time: 20:15. If the result crosses midnight, it shows the day offset (e.g., +1 day).

How do I calculate pay from hours worked?

In the Work Time mode, enter your shift times, break duration, and hourly rate. The calculator multiplies your net decimal hours by the rate. Example: 7.5 net hours × $25/hr = $187.50. This uses decimal hours for accuracy — 7 hours 30 minutes = 7.50, not 7.30.

Why is 1:30 not the same as 1.30 hours?

1:30 means 1 hour and 30 minutes (1.5 decimal hours), while 1.30 as a decimal means 1 hour and 18 minutes (0.30 × 60 = 18 minutes). This confusion is a common source of payroll errors. Always clarify whether a value is in HH:MM format or decimal hours.

How do I subtract time durations?

Enter both durations in HH:MM:SS and select the Subtract operation. The second duration is subtracted from the first. Example: 5:00:00 − 2:15:30 = 2:44:30. If the result is negative (the second duration is larger), the calculator shows a negative sign.

How many minutes are in a year?

A standard year has 525,600 minutes (365 days × 24 hours × 60 minutes). A leap year has 527,040 minutes (366 × 1,440). The calculator uses an average year of 365.25 days (525,960 minutes) to account for leap years in multi-year conversions.

Can I average multiple time durations?

Yes. In the Sum Multiple mode, the calculator automatically shows the average alongside the total. Enter all your durations (e.g., daily commute times) and the average appears in the results. Example: entries of 0:45, 1:10, 0:55 → total 2:50, average 0:56:40.

How do I track billable hours with this calculator?

Use the Sum Multiple mode to log each task with a label and duration. The total shows your billable hours, and the decimal hours value is ready for invoicing. Export to CSV for record-keeping. For a single work session, use Work Time mode with your hourly rate to see earnings directly.

Time Calculator

The Time Calculator is built for freelancers, shift workers, and project managers who need to add, subtract, or convert time durations in seconds — choose from 7 modes including work-hour tracking with pay, multi-duration summing, unit conversion, and "what time will it be in X hours." Use it whenever you're billing hourly, scheduling tasks across time zones, or breaking down a long shift. For differences between specific calendar dates, see the Date Calculator.

Time 1

Time 2

How to Add, Subtract & Sum Time Durations

Adding and subtracting time durations is one of the most common everyday calculations, yet doing it by hand often leads to errors because time uses a base-60 system instead of base-10. When you add 2 hours 45 minutes and 1 hour 30 minutes, the minutes column totals 75 — which means you need to carry 1 hour and keep 15 minutes, giving you 4 hours 15 minutes, not "3 hours 75 minutes."

This time calculator handles all the carry-over automatically. Enter durations in HH:MM:SS format, choose Add or Subtract, and get an instant result. For subtracting, the calculator supports negative results — useful when comparing estimated vs. actual time.

Practical Examples

Operation	Input	Result
Add two tasks	2:45:00 + 1:30:00	4:15:00
Add with seconds	1:15:30 + 0:50:45	2:06:15
Subtract break	8:00:00 − 0:45:00	7:15:00
Negative result	1:00:00 − 2:30:00	−1:30:00

Need to add more than two durations? Switch to the Sum Multiple mode, where you can enter as many rows as you need — perfect for weekly timesheets or project time tracking.

Calculating Time Between Two Clock Times

The "Time Between" mode calculates elapsed time from a start time to an end time. This is the go-to tool for figuring out how long a meeting lasted, how many hours you worked, or how much time remains until an event.

A key feature is overnight detection. If you enter a start time of 22:00 and an end time of 06:00, the calculator automatically recognizes this as an 8-hour overnight span rather than producing a negative result. An overnight indicator confirms when the calculation crosses midnight.

Common Use Cases

Scenario	Start	End	Duration
Standard workday	09:00	17:30	8h 30m
Morning shift	06:00	14:00	8h 00m
Night shift	22:00	06:30	8h 30m (overnight)
Short meeting	14:15	15:45	1h 30m

The result includes the duration in HH:MM:SS format plus decimal hours — a format widely used in payroll systems where 8 hours 30 minutes is expressed as 8.50 (not 8.30).

Work Time Calculator: Net Hours, Breaks & Earnings

The Work Time mode combines the "time between" calculation with break deduction and optional earnings estimation. Enter your shift start, shift end, break duration in minutes, and — optionally — your hourly rate to see exactly how much you earn per shift.

This mode is especially useful for hourly workers, freelancers, and anyone who needs to log billable hours. The calculator shows both gross hours (total time from start to end) and net hours (gross minus breaks), plus the decimal hours conversion that payroll systems require.

Example Calculations

Shift	Break	Gross	Net	Earnings ($25/hr)
08:00–16:30	30 min	8h 30m	8h 00m	$200.00
09:00–17:00	60 min	8h 00m	7h 00m	$175.00
22:00–06:00	30 min	8h 00m	7h 30m	$187.50
07:30–15:45	45 min	8h 15m	7h 30m	$187.50

Why decimal hours matter: Payroll systems multiply hours × rate as simple decimals. 7 hours 30 minutes is 7.50, not 7.30. This single confusion causes billing errors worth millions across the economy every year. The calculator always shows both formats so you can verify your timesheet entries.

Time Unit Converter: Seconds to Years

The Convert mode transforms any time value between seven units: seconds, minutes, hours, days, weeks, months, and years. Enter a value, select the source unit, pick the target unit, and the result appears instantly alongside a full breakdown in all units.

Quick Reference Table

From	To	Result
1 hour	minutes	60 minutes
1 day	hours	24 hours
1 week	hours	168 hours
1 year	days	365.25 days
1 year	hours	8,766 hours
1 year	minutes	525,960 minutes
90 minutes	hours	1.5 hours
10,000 seconds	hours	2.778 hours

For months and years, the calculator uses astronomical averages: 1 month = 30.4375 days, 1 year = 365.25 days (accounting for leap years). These are the standard values used in scientific and financial calculations.

Multiply, Divide & Average Time — Advanced Operations

Beyond basic addition and subtraction, three operations make the time calculator a powerful productivity tool:

Multiply Time answers "If one task takes X, how long do N tasks take?" For example, if one interview takes 45 minutes and you have 6 scheduled, the total is 45:00 × 6 = 4:30:00 (4 hours 30 minutes).

Divide Time answers "How long is each part?" If you have 3 hours to split equally among 4 team members, each gets 3:00:00 ÷ 4 = 0:45:00 (45 minutes each).

Average Time is calculated automatically in the Sum Multiple mode. Enter multiple durations — say, your daily commute times for a week — and the calculator returns both the total and the average. Example: commutes of 0:42, 0:55, 0:38, 0:51, 0:44 average to 0:46:00.

"What Time Will It Be?"

The "In X Hours" mode starts from any clock time and adds (or subtracts) a duration. Perfect for calculating delivery windows, cooking timers, or travel arrivals. Enter 14:30 as start, add 5 hours 45 minutes, and the result is 20:15. If the result crosses midnight, the calculator shows a day offset (e.g., +1 day or +2 days).

Common Uses for a Time Calculator

Work hours tracking — add up daily shifts or bill clients using the hours calculator
Shift scheduling — calculate duration calculator results across overnight or split shifts
Travel time planning — find the time difference between departure and arrival across time zones
Cooking & kitchen timers — sum multiple cooking durations to coordinate a full meal
Workout & training tracking — total intervals, rest periods, and session lengths
Project time estimation — break a project into tasks and sum the duration calculator results
Meeting scheduling — check what time a meeting ends given its start time and length
Freelance invoicing — convert decimal hours to H:M:S for accurate time difference billing

Time Calculator Examples with Real Numbers

Add time durations: 8:30 + 3h 45min

Start with 8 hours 30 minutes, add 3 hours 45 minutes using the hours calculator: 8h 30min + 3h 45min = 12h 15min. Useful for scheduling a meeting that starts at 8:30 AM and runs 3h 45min — it ends at 12:15 PM.

Time difference: 17:00 − 09:15

Use Mode 2 (Time Between) to compute the duration calculator result: 17:00 − 09:15 = 7h 45min (7.75 decimal hours). Ideal for payroll when you need the exact time difference for a standard working day.

Sum multiple durations: 2h 30min + 1h 15min + 45min

Enter three entries in Mode 3 (Sum Multiple): 2h 30min + 1h 15min + 0h 45min = 4h 30min. The bar chart shows each entry proportionally — great for project time estimation.

Work time with pay: 09:00–17:30, 45 min break, $35/h

Gross time: 8h 30min. Minus 45 min break = 7h 45min net (7.75 h). At $35/h that equals $271.25 earned. Mode 5 calculates this instantly.

Convert 1 week to hours

Switch to Mode 6 (Convert), enter 1 week → hours: 168 hours. The converter also shows minutes (10,080), seconds (604,800), and days (7) simultaneously.

How to Use the Time Calculator — Step by Step

Choose a mode — pick from 7 tabs: Add/Subtract, Time Between, Sum Multiple, Multiply/Divide, Work Time, Convert, or In X Hours.
Enter your values — input days, hours, minutes, and seconds (or use clock format HH:MM for time-of-day modes). Click "Now" to auto-fill the current time.
Click Calculate — results appear instantly in H:M:S and decimal hours format, plus total minutes and seconds.
Read the breakdown — for Work Time mode, see gross time, break deduction, net hours, and earnings. For Sum mode, a bar chart visualises each entry.
Export or save — download a CSV from Mode 3 (Sum Multiple), or rely on automatic localStorage to restore your last inputs next visit.

FAQ

How do I add hours and minutes together?: Enter each duration in HH:MM:SS format and use the Add operation. The calculator totals the seconds, carries over to minutes (every 60 seconds), then to hours (every 60 minutes). Example: 2:45:30 + 1:30:45 = 4:16:15.
How do I calculate hours between two times?: Enter the start and end clock times in the Time Between mode. The calculator subtracts start from end and returns the elapsed duration. Example: 09:00 to 17:30 = 8 hours 30 minutes. If the end time is earlier than the start, it assumes the next day (overnight shift).
What is decimal time and how do I convert it?: Decimal time expresses hours as a single number with a fractional part instead of HH:MM. For example, 1 hour 45 minutes = 1.75 decimal hours (45 ÷ 60 = 0.75). This format is commonly used for timesheets, payroll, and billing because it simplifies multiplication by hourly rates.
How do I calculate net work hours after breaks?: Use the Work Time mode: enter your shift start, shift end, and total break minutes. Net hours = gross hours minus break time. Example: start 08:00, end 16:30, 30-min break → gross 8h 30m, net 8h 00m. You can also enter an hourly rate to see your estimated earnings.
How do I multiply or divide a time duration?: Enter a duration (e.g., 1:30:00) and a factor. Multiply calculates repeated durations: 1:30:00 × 3 = 4:30:00. Divide splits a duration evenly: 6:00:00 ÷ 4 = 1:30:00. This is useful for estimating total time for repeated tasks or splitting time across team members.
How do I sum multiple time entries for a timesheet?: Use the Sum Multiple mode to add labeled time rows. Enter each task or day with its duration, then the calculator totals all entries and shows the sum plus an average per entry. You can also export the entries as a CSV file for your records.
How do I convert minutes to hours or hours to days?: Use the Convert mode. Select the source unit and target unit, enter the value, and the calculator shows the result plus a full breakdown in all units. Example: 150 minutes = 2.5 hours = 0.1042 days. Supported units: seconds, minutes, hours, days, weeks, months, and years.
How does the overnight time calculation work?: When the end time is earlier than the start time, the calculator automatically assumes the shift crosses midnight. It adds 24 hours to the end time before subtracting. Example: start 22:00, end 06:00 → 8 hours (not negative 16 hours). An overnight indicator flag confirms this adjustment.
What time will it be in X hours from now?: Use the "In X Hours" mode. Enter a start time (e.g., 14:30) and a duration to add (e.g., 5 hours 45 minutes). The calculator returns the future clock time: 20:15. If the result crosses midnight, it shows the day offset (e.g., +1 day).
How do I calculate pay from hours worked?: In the Work Time mode, enter your shift times, break duration, and hourly rate. The calculator multiplies your net decimal hours by the rate. Example: 7.5 net hours × $25/hr = $187.50. This uses decimal hours for accuracy — 7 hours 30 minutes = 7.50, not 7.30.
Why is 1:30 not the same as 1.30 hours?: 1:30 means 1 hour and 30 minutes (1.5 decimal hours), while 1.30 as a decimal means 1 hour and 18 minutes (0.30 × 60 = 18 minutes). This confusion is a common source of payroll errors. Always clarify whether a value is in HH:MM format or decimal hours.
How do I subtract time durations?: Enter both durations in HH:MM:SS and select the Subtract operation. The second duration is subtracted from the first. Example: 5:00:00 − 2:15:30 = 2:44:30. If the result is negative (the second duration is larger), the calculator shows a negative sign.
How many minutes are in a year?: A standard year has 525,600 minutes (365 days × 24 hours × 60 minutes). A leap year has 527,040 minutes (366 × 1,440). The calculator uses an average year of 365.25 days (525,960 minutes) to account for leap years in multi-year conversions.
Can I average multiple time durations?: Yes. In the Sum Multiple mode, the calculator automatically shows the average alongside the total. Enter all your durations (e.g., daily commute times) and the average appears in the results. Example: entries of 0:45, 1:10, 0:55 → total 2:50, average 0:56:40.
How do I track billable hours with this calculator?: Use the Sum Multiple mode to log each task with a label and duration. The total shows your billable hours, and the decimal hours value is ready for invoicing. Export to CSV for record-keeping. For a single work session, use Work Time mode with your hourly rate to see earnings directly.