Stopwatch (Duration Calculator)
Stopwatch (Duration Calculator) is a free online calculator that helps you format, add, or subtract durations like '1:23:45' or '1h 30m'. Heads up; this is a calculator, not a live stopwatch. Stopwatch (Duration Calculator) uses 3 input fields, returns 5 output values, and runs in your browser on the device.
Key facts
- Inputs
- 3 fields: Mode, Duration A, and Duration B
- Outputs
- 5 values: Result (HH:MM:SS), Human-readable, Total seconds, Total minutes, and Total hours
- Runtime
- your browser on the device
- Mode
- Calculator
- Privacy
- Files and text stay in the browser session.
- Cost
- $0, no account required
How to use Stopwatch (Duration Calculator)
- 1
Paste or fill in the input
Enter your text or values into the input fields on the page.
- 2
Run the utility
Click Compute to run the utility in your browser and review the result.
- 3
Copy the output
Copy the output value you need from the result panel.
Stopwatch (Duration Calculator) details
First, enter Mode in Stopwatch (Duration Calculator). Next, review Result (HH:MM:SS), Human-readable, Total seconds, Total minutes, and Total hours. Additionally, Stopwatch (Duration Calculator) uses 3 input fields and 5 output blocks so the result is easy to scan and copy.
Drop in durations in any common format ('1:23:45', '90:00', '1h 30m', '2.5h', '90s') and format, add, or subtract them. Output is given in HH:MM:SS, total seconds, and a human-readable form like '1h 30m 45s'. Heads up: this is a calculator, not a real-time stopwatch; for an interactive timer you can start and stop, use your phone's clock app. Stopwatch (Duration Calculator) is for the 'how long total did I spend on X' or 'what's 1h 25m plus 47 minutes' kind of question. Runs entirely in your browser.
Common searches
- stopwatch
- duration calculator
- time duration add
- time calculator
- add hours and minutes
- subtract time
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Frequently asked
What is Stopwatch (Duration Calculator)?
Stopwatch (Duration Calculator) is a free online calculator that helps you format, add, or subtract durations like '1:23:45' or '1h 30m'. Heads up; this is a calculator, not a live stopwatch. Stopwatch (Duration Calculator) uses 3 input fields, returns 5 output values, and runs in your browser on the device.
What inputs and outputs does Stopwatch (Duration Calculator) use?
Stopwatch (Duration Calculator) uses 3 input fields: Mode, Duration A, and Duration B. Stopwatch (Duration Calculator) returns 5 output values: Result (HH:MM:SS), Human-readable, Total seconds, Total minutes, and Total hours.
Do my files and data stay private?
Yes. Stopwatch (Duration Calculator) runs entirely in your browser using your device's CPU. Files and text are never uploaded to our servers, so your data stays private.
How do I use Stopwatch (Duration Calculator)?
Open Stopwatch (Duration Calculator), paste or fill in the input fields, and the result updates instantly. Stopwatch (Duration Calculator) runs in your browser with no upload and no waiting.
Which browsers does Stopwatch (Duration Calculator) support?
Any modern browser works in Chrome, Firefox, Safari, and Edge on desktop and mobile. Stopwatch (Duration Calculator) uses standard web APIs and does not require any plugin, extension, or sign-up.