A century represents an important period of time that allows us to understand and categorize history. But even though we often refer to “the 20th century” or “the 21st century”, some confusion remains over exactly how long a century is. This article will provide a complete breakdown of just what constitutes a century in years and help put this useful unit of time measurement into clear perspective.
Defining the Length of a Century
To start at the beginning, a century is defined as a period of 100 years. It is derived from the Latin terms “centum”, meaning 100, and “annus”, meaning year. A century is 10 times longer than a decade, which is a period of only 10 years.
So for a simple calculation:
100 years = 1 century 10 years = 1 decade
While we commonly think in decades or individual years when looking at shorter time frames, centuries are a useful for capturing the sweep and arc of history over longer stretches. The 100 year length provides a substantial period over which major events, trends, inventions and historical personalities can emerge and leave their mark.
Let’s look closer at the timespan covered when we refer to “the 1800s” or “the 1900s” for example…
When Do Centuries Start and Finish?
While a logical question, there is often confusion over what specific span of years is denoted by “the 18th century” versus “the 1800s” for example.
To clarify, centuries align with these start and end years:
- The 18th century covers the years 1701 to 1800
- The 19th century covers the years 1801 to 1900
- The 20th century covers the years 1901 to 2000
- The 21st century covers the years 2001 to 2100
So centuries begin at the ‘00 year and end at the ‘99 year, based on their numerical designations. The 1800s is referring to the 19th century, which runs from 1801 to 1900. And the 1900s denotes the 20th century, spanning 1901 to 2000. While we are currently in the early decades of the 21st century, which will continue all the way until the year 2100.
Understanding the years defining when centuries start & finish helps alleviate confusion when discussing noteworthy historical developments “of the 1800s” or speculating on future societal change “in the 2100s”. It provides clearer lineage and context.
Now that we understand the year coverage, just to reiterate…
How Many Years are in One Century?
While the prefixes make it fairly obvious (cent=100), it always bears repeating that:
There are 100 years in a century
Or more precisely for mathematical purposes:
Years in a Century Calculation:
1 century = 100 years
So if you ever need a quick reminder, whether looking back or projecting forward – a single century will always span exactly a 100 year period.
This consistent time length is what makes centuries so useful as a lens for examining patterns, social dynamics, and technological progress in history. Those 100 year blocks can neatly encapsulate distinct phases and “spirit of the age”.
Certain centuries like the 20th stand out…
Historical Significance of Centuries
Beyond just categorizing years, centuries also come to represent broader historical themes and pivotal developments in politics, culture, commerce and international relations. The 20th century for example harbored two world wars, the nuclear age, industrialization and the Digital Revolution.
By reflecting on defining moments & trends of past centuries, we gain deeper perspective on present day issues. And by extrapolating trajectories from prior centuries, we can also better speculate on possibilities of the century we find ourselves in. Will the 21st century witness more technological advancement? Further globalization and cooperation between nations? There are always lessons to be learned from history, and centuries provide an insightful framing.
While every century has its own significance and flavor, the table below profiles just a few of the more renowned past centuries and some of the notable events, inventions and accomplishments that occurred within their spans:
| Century | Major Occurrences |
|---|---|
| 19th Century | – Industrial Revolution begins |
| – Telegraph and railroad networks spread | |
| – Photography and telephone invented | |
| 20th Century | – Era of World Wars |
| – Penicillin, polio vaccine invented | |
| – Nuclear weapons developed | |
| – Moon landings, commercial air travel | |
| – Television, computers, and internet born |
Of course this just scratches the surface of the many prominent people, places and events that shaped these different centuries. But it provides a sampling of the watershed moments and breakthroughs that centuries can come to be known for based on clustering in their particular 100 year period.
Getting back to measurement, we’ve covered the 100 year length. But what about if we want even more precision…say calculating seconds in century?
Determining Seconds in a Century
For an even deeper conception of just how lengthy a century is, let’s determine the number of seconds in a century. This requires just a bit of straightforward math:
Steps to Determine Seconds in a Century
1) Calculate seconds in a year:
- 60 secs x 60 mins x 24 hours x 365 days = 31,536,000 seconds
2) Multiple seconds in a year by 100 years per century:
- 31,536,000 seconds x 100 years = 3,153,600,000 seconds
Result: There are 3,153,600,000 seconds in century span!
That’s over 3 billion seconds contained just within a single 100 year period! Going through this calculation gives one an appreciation for just how expansive a block of time a century occupies. Those seconds add up, even if they are just broken down into regular daily minutes while we are busy living our lives.
And based on geological and cosmological time scales, even centuries make up a tiny fraction of universal existence. Our human lifespans are but the blink of an eye relative to such immensities of time. However in our brief window, the capacity to organize and discuss centuries provides some sense of perspective.
With the length and parameters of centuries covered, as well as a taste of the varied events and personalities they encapsulate, let’s shift to some final thoughts…
Final Thoughts on Centuries
In closing, while we bandy about mentions of “the 60s” or “during the Enlightenment” or other century shorthand, having a firm handle on the concrete span of years they represent is useful for genuinely appreciating influence and accuracy. Not all centuries unfold similarly of course, but each one forms both an important chapter in overall human history while also laying foundations for subsequent periods.
Within their 100 year frames, centuries can capture wide spectra ranging from the Pax Romana to Mongol conquests to European colonization and modern technological disruption. They serve as helpful punctuation marks as we examine history in its grandest form. And as we march further into the 21st, comprehending the length and also potential promises of our current century can inspire reflection on where we’ve been as well as where we might aim to reach as a civilization in the decades ahead.
So while we all learned back in school that a century equates to 100 years, it never hurts to have a reminder. More so, internalizing just how expansive and dense with human activity those 100 year increments truly are provides helpful perspective. The decades of life we spend navigating personal, community and global events are all ingredients that will someday provide the “flavor” of the 21st century. Hopefully when our descendants one day look back on this period, it makes for an interesting and constructive read!
Frequently Asked Questions
- What is 50 years called?
- Half a century
- How many years are in a century?
- There are 100 years in a century
- When will the 21st century end?
- The 21st century will come to a close on December 31st, 2100