Time Converter

Convert between nanoseconds, milliseconds, seconds, minutes, hours, days, weeks, months, years, decades, and centuries.

Common Time Conversions
FromToResult
1 MinuteSeconds60 s
1 HourMinutes60 min
1 HourSeconds3,600 s
1 DayHours24 hr
1 WeekDays7 days
1 YearDays365.25 days
1 YearSeconds31,557,600 s
1 CenturyYears100 years

Frequently Asked Questions

A Julian year (used in astronomy) is exactly 31,557,600 seconds = 365.25 days × 24 hr × 3600 s. A calendar year has 365 days = 31,536,000 s, or 366 days in a leap year = 31,622,400 s. This converter uses the Julian year for consistency.

An average month is 365.25/12 = 30.4375 days = 2,629,800 seconds. Individual months range from 28 to 31 days. This converter uses the average month value for general purpose conversions rather than a specific calendar month.

A nanosecond is one billionth of a second (10⁻⁹ s). It is commonly used in computing — for example, RAM access times are measured in nanoseconds, and modern CPUs execute billions of clock cycles per second. Light travels about 30 cm in one nanosecond.

A calendar year has 52 weeks plus 1 day (or 2 days in a leap year), totaling 52.18 weeks on average. A Julian year = 365.25 days / 7 = 52.1786 weeks. ISO 8601 defines the week numbering system where some years can have 53 ISO weeks.

A common calendar year has 31,536,000 seconds (365 × 24 × 3600). A leap year has 31,622,400 seconds. The Julian year used in astronomy has 31,557,600 seconds (365.25 days). A useful approximation: π × 10⁷ ≈ 31,415,927 seconds — accurate to within 0.4% of a calendar year.

A month averages 4.345 weeks (30.4375 days ÷ 7). Calendar months vary from 28 to 31 days, so the number of complete weeks ranges from 4 to 4.43. For payroll and financial calculations, months are often estimated as 4.33 weeks or 30 days rather than a precise number of weeks.

A millisecond is one thousandth of a second (10⁻³ s). It is commonly used in computing (network ping latency, mouse click response), gaming (frame render times), medicine (cardiac electrical pulses), and photography (flash duration). Human reaction time averages about 200–250 milliseconds.

A Unix timestamp is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC (the "Unix epoch"). It is widely used in programming to represent points in time as a single integer. For example, 1,700,000,000 corresponds to November 14, 2023. Millisecond-precision timestamps divide by 1,000 to get the Unix timestamp.

A UTC offset is a fixed difference from UTC (e.g., UTC+5:30 for India Standard Time). A time zone is a named region that may change its UTC offset seasonally due to Daylight Saving Time. For example, New York is UTC−5 in winter (EST) and UTC−4 in summer (EDT). UTC offsets are simpler but time zones are more accurate for scheduling.

Business days are typically Monday through Friday, excluding weekends and public holidays. In a standard week there are 5 business days. A month averages about 21–22 business days. Business day calculations matter for contracts, shipping estimates, and financial settlements (e.g., stock trades settle T+2 business days).

About This Time Converter

This free time converter converts between seconds, minutes, hours, days, weeks, months, and years. Enter a duration in any unit and all others update instantly.

When to use this converter

  • Converting server uptime or SLA duration metrics
  • Calculating project durations across different time units
  • Comparing time periods expressed in different scales

How It Works

Enter Time Value

Type any time value from nanoseconds to centuries. Conversions use the second as the SI base unit.

Choose Time Units

Select from 12 time units spanning from nanoseconds to centuries. Average values are used for months and years.

Instant Conversion

Results are shown in real time. Swap the direction instantly with the swap button.

Common Use Cases

Software Development

Convert between milliseconds, seconds, and hours for API timeouts, cache expiry, job scheduling, and performance benchmarks.

Project Planning

Convert project durations between days, weeks, and months for sprint planning, deadline calculations, and milestone tracking.

Computing & Hardware

Convert CPU cycles, memory latencies, and network round-trip times between nanoseconds, microseconds, and milliseconds.

Sports Timing

Convert race times and athletic records between milliseconds, seconds, minutes, and hours for comparison across different events.

Science & Research

Convert time intervals for physics experiments, chemistry reactions, and astronomical observations across different time scales.

Finance & Contracts

Convert contract durations and financial periods between days, months, and years for loan calculations, lease terms, and interest periods.

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