# Time calculator: add and subtract hours and minutes

> Add and subtract hours, minutes and seconds from a list of durations, with the total as H:MM:SS, decimal hours, minutes and seconds.

انٹرایکٹو صورت: https://www.calcopenly.com/ur/datetime/time-duration-calculator
موضوع: تاریخ اور وقت کے کیلکولیٹر

Each line is converted to seconds (3,600 × hours + 60 × minutes + seconds), lines that start with a minus sign are subtracted, and the sum is turned back into hours, minutes and seconds. Entries can be written as H:MM:SS, H:MM, 2h 15m, 90 min or 1.5 h. The total is a duration, not a time of day, so 23:59:59 plus one second gives 24:00:00 rather than wrapping to midnight.

Typical uses are adding up timesheet entries, video clip lengths, lap splits and flight legs. The default list, 1:45:30 plus 2:20:15 minus 0:30:00, totals 3:35:45, which is 3.5958 decimal hours or 215.75 minutes.

Decimal hours are the total seconds divided by 3,600, the form payroll and invoicing systems usually ask for: 7 hours 45 minutes is 7.75 hours. To find the time between a start and an end time of day, use the hours calculator instead.

## اندراجات

- **Durations, one per line**: H:MM:SS or H:MM, or 2h 15m, 90 min, 1.5 h. Start a line with − to subtract it.

## نتائج

- Total — بنیادی نتیجہ
- Total as H:MM:SS
- Decimal hours (h)
- Total minutes (min)
- Total seconds (s)

## فارمولا

$$
T = \sum_i \pm (3600\,h_i + 60\,m_i + s_i)\ \text{s},\qquad \text{decimal hours} = T / 3600
$$

## حل شدہ مثالیں

### Two additions and a subtraction

- Durations, one per line: 1:45:30 / 2:20:15 / - 0:30:00
- **Total: 3 h 35 min 45 s**
- **Total as H:MM:SS: 3:35:45**
- **Decimal hours: 3.5958 h**
- جانچ کا ماخذ: ⁨Python fractions: (6330 + 8415 − 1800) s = 12945 s = 3 h 35 min 45 s; 12945/3600 = 3.5958333…⁩

### Carrying past 24 hours

- Durations, one per line: 23:59:59 / 0:00:01
- **Total: 1 d**
- **Total as H:MM:SS: 24:00:00**
- **Decimal hours: 24 h**
- جانچ کا ماخذ: ⁨86399 + 1 = 86400 s by hand⁩

### A negative total

- Durations, one per line: 1:00 / - 2:30
- **Total: −1 h 30 min**
- **Total as H:MM:SS: −1:30:00**
- **Decimal hours: -1.5 h**
- جانچ کا ماخذ: ⁨3600 − 9000 = −5400 s by hand⁩

### Mixed notations

- Durations, one per line: 90 min / 1.5 h / 45 s
- **Total: 3 h 45 s**
- **Total minutes: 180.75 min**
- جانچ کا ماخذ: ⁨5400 + 5400 + 45 = 10845 s; 10845 / 60 = 180.75 by hand⁩

## سوالات

### How do I add hours and minutes together?

Add the hours and the minutes separately, then carry every 60 minutes into an hour. 1:45 plus 2:20 gives 3 hours and 65 minutes, and 65 minutes is 1 hour 5 minutes, so the total is 4:05. Seconds carry into minutes the same way. Typing each duration on its own line here does the carrying for you.

### How do I convert minutes to decimal hours?

Divide the minutes by 60. 15 minutes is 0.25 hours, 45 minutes is 0.75 hours, so 7 hours 45 minutes is 7.75 hours, and 3:35:45 is 12,945 ÷ 3,600 = 3.5958 hours. When a timesheet rounds to two decimals, each 0.01 hour is 36 seconds, so 3.5958 is entered as 3.60.

### How do I convert decimal hours back to hours and minutes?

Keep the whole hours and multiply the decimal part by 60 to get minutes. 1.5 hours is 1 hour 30 minutes, 3.6 hours is 3 hours 36 minutes and 0.1 hours is 6 minutes. Type an entry such as 3.6 h on a line here to see it shown as 3:36:00.

### How do I subtract one time duration from another?

Start the line with a minus sign. If the minutes to take away are larger, borrow 60 minutes from the hours: 2:10 minus 0:45 becomes 1:70 minus 0:45, which is 1:25. The total can go below zero; 1:00 minus 2:30 gives −1:30:00, an hour and a half short.

### How do I add times in Excel without the total resetting at 24 hours?

Excel stores a time as a fraction of a day, so a plain h:mm format wraps after 24 hours and 25 hours shows as 1:00. Format the total cell with the custom format [h]:mm:ss and the square brackets let hours run past 24. To get decimal hours in Excel, multiply the time by 24.

### “⁨Time calculator: add and subtract hours and minutes⁩” کتنا درست ہے؟

درستی آپ کی درج کردہ قدروں اور طریقے کے مفروضوں پر منحصر ہے۔ اعشاری حساب 50 بامعنی ہندسے استعمال کرتا ہے، مگر تخمینے، عددی طریقے اور ماخذ کا ڈیٹا کم درست ہو سکتے ہیں؛ دکھائی گئی قدروں کو راؤنڈ کرنے سے یہ حدود ختم نہیں ہوتیں۔ آزاد ذرائع کی حل شدہ مثالوں سے جانچ: 4۔ مثلاً، “⁨Two additions and a subtraction⁩” کو ⁨Python fractions: (6330 + 8415 − 1800) s = 12945 s = 3 h 35 min 45 s; 12945/3600 = 3.5958333…⁩ سے جانچا جاتا ہے۔

### اس طریقے کا ماخذ کیا ہے؟

ISO 8601-1:2019 — durations and the extended time format hh:mm:ss; BIPM, The International System of Units (SI), 9th ed. — minute and hour as non-SI units accepted for use with the SI.

## ماخذ

- ISO 8601-1:2019 — durations and the extended time format hh:mm:ss
- [BIPM, The International System of Units (SI), 9th ed. — minute and hour as non-SI units accepted for use with the SI](https://www.bipm.org/en/publications/si-brochure)