Time Converter
Convert time between nanoseconds, microseconds, milliseconds, seconds, minutes, hours, days, weeks, and years.
How to use this tool
- Enter time and from unit in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your minutes and the full breakdown beneath it.
Formula
All durations are normalised to seconds, then converted to each output unit:
seconds = value × factorfrom
Key factors: 1 ns = 10⁻⁹ s, 1 µs = 10⁻⁶ s, 1 ms = 0.001 s, 1 min = 60 s, 1 h = 3,600 s, 1 day = 86,400 s, 1 week = 604,800 s, 1 year = 31,557,600 s (Julian year: 365.25 days).
How it works
The converter uses seconds as its base unit. The input is multiplied by the appropriate seconds-per-unit factor to get a raw second count, which is then divided by each output unit's factor. The year is defined as the Julian year of exactly 365.25 days (31,557,600 seconds), a standard used in astronomy and physics.
Common mistake: Assuming one year equals exactly 365 days. A Julian year is 365.25 days (31,557,600 s), a Gregorian calendar year averages 365.2425 days, and a tropical solar year is approximately 365.24219 days. Using 365 days for multi-year calculations introduces a growing error of about 6 hours per year.
Worked example
Convert 1 hour to all time units
- Input: 1 hour. Factor for hour = 3,600 s.
- Base seconds = 1 × 3,600 = 3,600 s.
- ns = 3,600 / 10⁻⁹ = 3,600,000,000,000; µs = 3,600,000,000; ms = 3,600,000; min = 3,600 / 60 = 60.
- Days = 3,600 / 86,400 ≈ 0.04167; weeks ≈ 0.005952; years = 3,600 / 31,557,600 ≈ 0.0001141.
1 hour = 3,600,000,000,000 ns = 3,600,000,000 µs = 3,600,000 ms = 3,600 s = 60 min = 1 h ≈ 0.04167 days ≈ 0.005952 weeks ≈ 0.0001141 years.
Common mistakes to avoid
- Assuming 1 year = 365 days exactly -- this tool uses 365.25 days to approximate the mean Julian year; results involving years are estimates because calendar years vary (365 or 366 days).
- Confusing milliseconds and microseconds -- 1 ms = 1,000 us; swapping them in network latency or audio sample rate calculations produces errors of 1,000x.
- Using days when the calculation spans daylight saving time changes -- a calendar day near a DST transition can be 23 or 25 hours, so converting by multiplying days by 86,400 seconds may be off by an hour.
Key terms
- Nanosecond (ns)
- One billionth of a second (10⁻⁹ s). Relevant in computing for processor clock cycles, memory latency, and signal propagation in electronic circuits.
- Julian year
- Exactly 365.25 days, or 31,557,600 seconds. Used as the standard year length in astronomy and physics to avoid ambiguity between calendar year types.
- Microsecond (µs)
- One millionth of a second (10⁻⁶ s). Common in networking (ping latency is often in hundreds of microseconds) and in scientific instrumentation.
- Week
- A period of exactly 7 days, or 604,800 seconds. Unlike months and years, a week has a fixed, unambiguous duration in seconds.
Frequently asked questions
- How many seconds are in a year?
- Using 365.25 days per year: 365.25 x 24 x 60 x 60 = 31,557,600 seconds per Julian year. A common approximation is 31.5 million seconds or roughly pi x 10^7 seconds.
- What is a nanosecond used for?
- Nanoseconds (10^-9 seconds) appear in CPU clock speeds, memory access times, and signal propagation delays. Light travels about 30 cm in one nanosecond, which matters in chip design and network time synchronization.
- Why does 1 week not always equal exactly 7 x 24 hours in practice?
- In practice it does, but civil time can insert or remove seconds (leap seconds) to keep UTC aligned with Earth rotation. For everyday conversions, 1 week = 604,800 seconds is accurate enough.