Convert Time from Month to Year (month to year)

Month to Year Conversion Formula

To convert from Month (month) to Year (year), use the following formula:

Example

Let's convert 5 Month (month) to Year (year).

Using the formula:

Therefore, 5 Month (month) is equal to $0.41666666666666666667$ Year (year).

What is a Month?

A month is a unit of time we use in our calendars, lasting from 28 to 31 days.

While it's a simple concept we use every day, the story of the month is a fascinating blend of astronomy and ancient history, tied directly to the Moon's cycle.

Why Is a Month About 30 Days Long?

The concept of a month is fundamentally tied to the Moon. A "lunar month" (or synodic month) is the time it takes for the Moon to cycle through all its phases, from one new Moon to the next, which is approximately 29.5 days.

Early civilizations built their calendars around this observable cycle. However, because 12 lunar months (~354 days) don't perfectly align with a full solar year (~365.25 days), calendar months were adjusted to their current, slightly longer, and more varied lengths to keep the seasons in sync with the year.

Where Do the Names of the Months Come From?

Many of our modern month names are inherited from the ancient Roman calendar, which initially had only ten months and started in March. This is why the names for September, October, November, and December come from the Latin words for seven, eight, nine, and ten, respectively.

Later, January (named for Janus, the god of beginnings) and February were added. Months like March were named for the god Mars, while July and August were renamed to honor the influential Roman leaders Julius Caesar and Augustus Caesar.

Why Do Months Have Different Numbers of Days?

The irregular pattern of 28, 30, and 31 days in a month is the result of historical calendar reforms. When the Romans moved from a lunar-based to a solar-based calendar, they needed to spread the days of the year across 12 months.

The system we use today, the Gregorian calendar, is a refinement of the Julian calendar established by Julius Caesar. The specific lengths were a practical solution to make 365 days (and later, 365.25 with a leap day) fit into 12 divisions.

February was left with the fewest days, partly because it was the last month added to the original Roman calendar.

What is a Year (year)?

A year is the time it takes for the Earth to complete one full orbit around the Sun.

We commonly think of a year as 365 days, but it's not quite that simple. The Earth's journey actually takes a little longer, which is why our calendar needs a special trick to stay accurate.

Why Do We Have Leap Years?

The Earth takes approximately 365.24 days to travel around the Sun. That extra quarter of a day might not seem like much, but it adds up over time.

To keep our calendar in sync with the Earth's orbit and the seasons, we add an extra day—February 29th—nearly every four years. This is called a leap year.

Without leap years, our calendar would drift by about 24 days every 100 years, and eventually, we'd have summer in December!

Are There Different Types of Years?

Yes! While our calendar uses a 365-day system, scientists use more precise measurements depending on what they're tracking.

The two most common types of years are:

• The Tropical Year (The Year of Seasons): This is the year our calendar is based on. It's the time from one spring equinox to the next, lasting about 365.2422 days. It ensures that spring, summer, fall, and winter always happen in the same months.
• The Sidereal Year (The Star Year): This is the time it takes for Earth to complete one full orbit around the Sun relative to the distant stars. It's slightly longer than a tropical year at 365.2563 days—about 20 minutes longer.

What is a Galactic Year?

The idea of a "year" can get much, much bigger. Just as the Earth orbits the Sun, our entire solar system orbits the center of the Milky Way galaxy.

This enormous journey is called a Galactic Year (or cosmic year), and it takes an estimated 230 million Earth years to complete. To put that in perspective, the last time our solar system was in this exact spot, dinosaurs were beginning to roam the Earth during the Triassic period.

What is the International System of Units (SI)?

Month to Year Conversion Table

Here are some quick reference conversions from Month (month) to Year (year):