A+ PrimeForYou

Sense of Scale — A Visual Journey from 1 to Infinity

1

You Are Here

Every journey begins with a single number.

0 second Counting one number per second...
10

Count Your Fingers and Toes

These are the first numbers we learn to grasp. 4 of these are prime.

0 seconds A quick count.
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100

A Centurion’s Count

A lifetime measured in years. 25 of these are prime — exactly one in four.

0 seconds 1 minute, 40 seconds
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1,000

A Grand Total

168 primes hide here. As numbers grow, the primes already begin to thin out.

0 seconds 16 minutes, 40 seconds
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10⁶

One in a Million

The estimated odds of being struck by lightning this year.

0 days A week and a half.
10⁹

One in a Billion

A modern computer can find every prime below here in under a second.

0 years An entire generation.
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10¹⁶

The Age of the Forest

Roughly the number of seconds since the first trees appeared on Earth, 317 million years ago.

0 years Since the first forests.
10¹⁸

Every Grain of Sand

Roughly the number of grains of sand on every beach on Earth.

0 × the age of the universe
10¹⁹

Beyond Reasonable Doubt

The chance of a prime-testing error is less than a meteorite hitting your home.

0 × the age of the universe
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10³⁸

Your Prime Lives Here

In the 128-bit space of our registry, your prime is one of undecillions.

0 Even the universe can’t count this high.
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10⁸⁰

Every Atom in the Universe

The total number of atoms in the entire observable universe.

Numbers beyond time.
41M digits

The Largest Known Prime

If printed, it would stretch 65 miles. It would take 1.3 years just to write it out.

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The Infinite Horizon

Euclid proved 2,300 years ago that the primes never, ever stop.

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