You've probably heard the word "googol" and immediately thought of the search engine. That's fair. But the actual number, 10 to the 100, is a monster that defies human intuition in ways that make "billions and trillions" look like pocket change. It is a 1 followed by a hundred zeros. It's $10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000$.
Honestly, writing it out is exhausting. But understanding it? That's a different beast entirely.
The term was coined back in 1920 by a nine-year-old kid named Milton Sirotta. His uncle was the mathematician Edward Kasner. Kasner wanted a name for a staggeringly large number to help students grasp the difference between "infinite" and "just really, really big." Milton suggested "googol," and it stuck. It’s a bit ironic that a word born from a child’s imagination now defines the scale of modern computational limits and the eventual heat death of our universe.
People get it wrong all the time. They think a googol is roughly equivalent to the atoms in the universe. It isn't. It's much, much bigger.
The scale of 10 to the 100 vs. reality
To understand 10 to the 100, you have to realize that our brains aren't wired for exponential growth. We do okay with linear stuff—if you walk twenty miles, you’re tired. If you walk forty, you’re twice as tired. But exponents are a whole other game.
Let's look at the observable universe. Most cosmologists, including the likes of Neil deGrasse Tyson or the late Stephen Hawking, estimate there are about $10^{80}$ atoms in the observable universe. Think about that for a second. $10^{80}$. That is a 1 with 80 zeros.
If you take every single atom in every star in every galaxy we can see, you are still 20 orders of magnitude short of a googol. In math terms, a googol is $10^{20}$ times larger than the number of atoms in the universe. To put it in a way that actually makes sense: if you had a hundred million trillion "observable universes," the total number of atoms in all of them combined would finally equal one googol.
It’s basically an impossible amount of stuff.
Why computer scientists care about this number
You might wonder why we even bother with a number this big if it doesn't describe the physical world. In the world of technology and cryptography, 10 to the 100 is a vital benchmark. It’s often used to describe the "search space" of certain problems.
Take a standard 256-bit AES encryption key. This is the stuff that secures your bank transfers and private messages. The number of possible combinations for a 256-bit key is roughly $1.1 \times 10^{77}$. That is significantly less than a googol. When security experts talk about "brute-forcing" a password, they are looking at these massive numbers. If a computer could try a trillion combinations every second, it would still take trillions of years to crack.
The googol represents a "wall." It’s a point where, for all practical purposes, a number becomes so large that even the fastest possible computer—operating at the physical limits of matter—couldn't finish a task before the sun burns out.
The Google connection and the typo that changed history
It’s the most famous typo in business history. In 1996, Larry Page and Sergey Brin were working on a search engine at Stanford. They originally called it BackRub. Thankfully, they realized that was a terrible name.
They wanted something that signified the massive amount of data they were indexing. They landed on "googol." However, when Sean Anderson, a fellow graduate student, searched to see if the domain name was available, he accidentally typed "https://www.google.com/search?q=google.com" instead of "https://www.google.com/search?q=googol.com." Page liked the misspelling better.
Basically, the multi-trillion-dollar company we use every day is named after a spelling error of 10 to the 100.
Does Google actually index a googol of pages?
Not even close.
👉 See also: Who is the Inventor of Ballpoint Pen? The Messy History of How We Really Started Writing
While the web is massive, it’s not that massive. As of 2024 and 2025, estimates suggest the indexed web is in the hundreds of billions of pages. Even if you count every unique URL ever generated, you’re likely still under $10^{15}$ or $10^{20}$. To reach a googol, the internet would have to grow by a factor that is, frankly, inconceivable.
10 to the 100 and the end of everything
Theoretical physics is where 10 to the 100 gets really spooky. If you look at the timeline of the universe, we are currently living in the "Stelliferous Era"—the age of stars. But stars don't last forever. Eventually, they’ll all burn out.
Cosmologists like Katie Mack have written extensively about the "Heat Death" of the universe. In the very, very distant future, the only things left will be black holes. These black holes will eventually evaporate due to something called Hawking Radiation.
How long does that take?
For a supermassive black hole at the center of a galaxy to completely evaporate, it takes roughly $10^{100}$ years. That is one googol years. It’s a timescale so vast that the entire history of our universe so far—about 13.8 billion years—is just a microscopic blink at the very beginning.
When people talk about 10 to the 100, they aren't just talking about a big number. They are talking about the "Time of the Black Holes." Once those $10^{100}$ years have passed, the universe will effectively be empty. No light, no heat, just a thin soup of subatomic particles drifting through an endless void.
The Googolplex: Going even further
If 10 to the 100 isn't enough for you, there’s the googolplex.
👉 See also: Snapchat Boomerang: Why Your Loops Look Bad and How to Fix Them
A googolplex is 10 to the power of a googol. That is a 1 followed by a googol of zeros.
Edward Kasner used to joke that a googolplex is so large that if you tried to write it down, you’d run out of room in the entire universe. He wasn't exaggerating. Even if you could write zeros on every single atom in the observable universe, you’d run out of atoms long before you finished writing the zeros in a googolplex.
It’s a fun mental exercise, but it also highlights a limit of physical reality. There is a point where math outstrips the ability of the physical universe to contain it.
Misconceptions about large numbers
A lot of people confuse a googol with "infinity." They aren't the same.
- Infinity is a concept, not a number. You can't reach it.
- A googol is a finite integer. It is odd or even (it’s even). It has a square root. You can add 1 to it.
Another common mistake is the "Borel's Law" argument. Some mathematicians argue that any event with a probability of less than 1 in $10^{50}$ is "practically impossible." Since a googol is $10^{100}$, an event with a 1 in a googol chance is so unlikely that it would probably never happen in the entire history of the universe, even if you ran the experiment every nanosecond.
What you can actually do with this knowledge
Understanding the scale of 10 to the 100 isn't just for trivia night. It changes how you view data, security, and the sheer scale of the world.
Verify your security. Knowing that 256-bit encryption relies on numbers approaching the scale of a googol should give you some peace of mind regarding digital privacy. If your password manager uses this level of encryption, it's mathematically "safe" from brute force.
Think exponentially. Most business failures happen because people expect linear growth and get blindsided by exponential decay or vice versa. When you see a number like 10 to the 100, let it serve as a reminder that small changes in an exponent lead to world-altering results.
Explore the "Big Number" community. If you find this fascinating, look up "Graham's Number" or "TREE(3)." These are numbers that make a googolplex look like a zero. They are used in Ramsey Theory and other complex branches of mathematics to solve specific, albeit abstract, problems.
Calculate your own "unlikely" odds. Use the concept of the googol to put your daily worries in perspective. The odds of you existing, given the specific sequence of DNA and historical events required, are statistically "impossible," yet here you are.
To really wrap your head around this, try using a scientific calculator to perform operations with exponents. You'll quickly see the "Error" message once you cross certain thresholds. That's not just a limitation of the software; it's a reflection of the fact that, for almost everything in our human experience, a googol is effectively the end of the world.
Next Steps for Exploration:
- Check your digital accounts to ensure they use AES-256 encryption, which leverages the mathematical "walls" discussed here.
- Read The End of Everything (Astrophysically Speaking) by Katie Mack for a deeper look at the $10^{100}$ year timeline of the universe.
- Experiment with a "Big Number" calculator online to see how quickly $10^{x}$ outpaces any physical quantity you can name.