Time Unit Converter

Convert between units of time.

Supported Units

• Year (yr): In the Gregorian calendar, one year averages 365.2425 days, which equals exactly 31,556,952 seconds. The Gregorian calendar was introduced by Pope Gregory XIII in 1582, refining the Julian calendar with a leap-year rule that skips century years not divisible by 400. The year is the fundamental unit for measuring human age, academic terms, fiscal periods, and historical timelines. In astronomy, the light-year—the distance light travels in one year—is used to measure vast cosmic distances.
• Month (mo): For conversion purposes, one month is defined as 30.436875 days (365.2425 ÷ 12), or exactly 2,629,746 seconds. While actual calendar months range from 28 to 31 days, this average provides a consistent basis for calculation. Salaries, rent, subscriptions, and loan payments are typically structured on a monthly cycle. Pregnancy duration is commonly described in months, and project timelines in business often use months as their primary planning unit.
• Week (wk): A week consists of 7 days, or exactly 604,800 seconds. The seven-day cycle has ancient origins, often attributed to the Babylonians who divided the roughly 29.5-day lunar month into four parts. Today, the week structures the rhythm of work, school, and social life across most cultures, with the common pattern of five workdays and a two-day weekend. Phrases like "this weekend," "biweekly," and "next week" are among the most frequently used time references in daily conversation.
• Day (d): A day is defined as exactly 24 hours, or 86,400 seconds. It is based on the time it takes for the Earth to complete one rotation relative to the Sun (a solar day) and is one of the oldest units of time recognized by humans. The day governs the circadian rhythm of virtually all living organisms, cycling between wakefulness and sleep. Travel itineraries, medication schedules, food expiration dates, and countless other aspects of daily life are organized around this fundamental unit.
• Hour (h): An hour is 60 minutes, or exactly 3,600 seconds. The division of the day into 24 hours dates back to ancient Egypt, where daytime and nighttime were each split into 12 parts. Hours are used to measure work shifts, class periods, movie durations, and travel times. Speed is expressed as distance per hour (km/h or mph), and hourly wages are a common form of compensation. The hour strikes a practical balance between the day and the minute for scheduling and timekeeping.
• Minute (min): A minute is 60 seconds. The concept originates from the Babylonian sexagesimal (base-60) numeral system, and the same term is used for one-sixtieth of a degree in geometry and navigation. Minutes are ubiquitous in daily life: cooking timers, bus and train schedules, meeting agendas, and workout intervals are all measured in minutes. Expressions like "a five-minute walk" and "just a minute" are among the most common time references in everyday speech.
• Second (s): The second is the base unit of time in the International System of Units (SI). Originally defined as 1/86,400 of a mean solar day, it has been defined since 1967 by the radiation corresponding to 9,192,631,770 periods of the cesium-133 atom's ground-state hyperfine transition. Seconds are essential for precise timing in athletics, traffic signals, heart-rate monitoring, and scientific experiments. In computing and networking, latency and response times are measured in seconds or milliseconds.
• Millisecond (ms): A millisecond is one-thousandth of a second. A human eye blink takes roughly 100 to 400 milliseconds, and camera shutter speeds are often measured in milliseconds. In computer science, network latency (ping times), database query response times, and animation frame intervals are all tracked in milliseconds. In music production, MIDI timing adjustments and audio synchronization require millisecond-level precision. Financial trading systems also operate on millisecond timescales to execute high-frequency transactions.

How to Use

1. Select the unit you want to convert from in the "From" dropdown.

2. Select the unit you want to convert to in the "To" dropdown.

3. Enter a value and the result will be displayed in real time.

4. Use the swap button to reverse the conversion direction.