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Tongue twister: The number of possible IPv6 addresses read out loud

IPv6 can theoretically hold 2^128 IP addresses. As you’re probably aware of, that’s a huge number:

2^128 = 340,282,366,920,938,463,463,374,607,431,768,211,456

Have you ever wondered how you would actually SAY that number if you had to read it out loud? A cool thing with Wolfram Alpha is that it will spell out numbers for you, making it possible for us to find this out without too much of a headache. Here’s the text version of the number:

340 undecillion, 282 decillion, 366 nonillion, 920 octillion, 938 septillion, 463 sextillion, 463 quintillion, 374 quadrillion, 607 trillion, 431 billion, 768 million, 211 thousand and 456

Read it out loud really fast. A bit of a mouthful… :)

We write about IPv6 from time to time in this blog. You might want to check out a couple of our previous articles:


If we ever have to switch to IPv8, we’ll know for sure there are too many computers in the world.

crap! we ran out of ip addresses!

Proper grammar wouldn’t include an “and” before 456.

For correct verbalization, the word “AND” should be used only to denote the location of the decimal, as in 100.21 would be one-hundred and 21 cents, (or hundredths), etc.

Gabriel Olson

May 9th, 2012 at 4:12 pm

How does this number compare to the number of stars in the universe, or even better, the number of atoms in the universe (estimated, of course)?

If only our cable providers would allocate some to us :)

David Riesenberg

May 9th, 2012 at 4:12 pm

According to Wikipedia, the estimated numbers of atoms in the universe is ~10^80, or 100 quinvigintillion

That’s a lot of websites for us to write about. Gulp.