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Time Conversion

Convert between seconds, minutes, hours, days, and weeks; add/subtract times; format HH:MM:SS; and compute date-time differences.

Educational tool — approximations used for months/years.

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FAQs

Frequently Asked Questions

Do months/years have fixed lengths here?

Months/years vary in real life. If selected in date-time difference calculations, we use a standard approximation (30.4375 days per month, 365.25 days per year) for educational purposes.

Can I input times over 24 hours in HH:MM:SS?

Yes—enable the 'Allow overflow' option to treat HH as hours in a duration, not a clock cap. This allows durations like '25:30:00' for 25 hours and 30 minutes.

How do time zones affect results?

For date-time differences, we convert both datetimes to UTC internally for accurate calculations. You can choose the display time zone in the epoch/ISO converter.

Does it handle leap seconds?

Not by default. For educational focus, we ignore leap seconds and use standard time conversions (60 seconds = 1 minute, etc.).

Can I paste '1h 30m 45s'?

Yes! In the Time Arithmetic operation, you can use freeform time formats like '1h 30m', '90m', '01:30:45', or combinations. The parser recognizes common patterns automatically.

What precision should I use?

For unit conversions, choose precision (0-6 decimals) based on your needs. Higher precision is useful for scientific calculations, while lower precision is fine for general use.

How accurate is the date-time difference?

The calculation uses JavaScript Date objects which handle time zones and daylight saving time. For exact precision, results are shown in seconds, with approximate breakdowns for years/months.

Can I convert negative times?

Yes, in arithmetic operations (subtraction) and date-time differences when absolute mode is off, negative results are supported and displayed correctly.

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Time Conversion | EverydayBudd