Tag Archives: IP

How many IPv6 addresses are there? Answer: a lot

How many IPv6 addresses are there? This would make an epic pub quiz question…not quite as epic as its answer though.

Over the years when learning about computer networking, one of the big issues has been how we are running out of the addresses that our devices use on the internet, the main addresses we use on the Internet are IPv4 addresses, of which there are 4.3 Billion, quite a large number, but despite huge efforts to preserve them they have completely run out!

So because of this we had to introduce a new type of addressing, one that won’t run out, this is called IPv6, and there are a lot of these addresses, so many that the boffins are willing to bet their last pair of brown cord trousers that we will never run out of them, now whenever you read about IPv6 in the big heavy dull textbooks the bit where they tell you how many of these addresses there actually are, is always represented in the correct mathematical notation, they will tell you that there are 2 ^128, or 3.4×10^38 unique addresses. Today I was thinking about what that number actually looks like and how you would actually say it aloud if you had to answer how many IPv6 addresses there are in a pub quiz, so I went and found out…so are you ready for this, altogether now, say it along with your friends and family there are, 340,282,366,920,938,463,463,374,607,431,768,211,456 unique IPv6 addresses.

OK, that wasn’t fair, I couldn’t have worked out how to say it aloud either, but thankfully someone way smarter than me did, so if you were to speak that number aloud you would have to say…now take a deep breath:

three hundred forty undecillion, two hundred eighty-two decillion, three hundred sixty-six nonillion, nine hundred twenty octillion, nine hundred thirty-eight septillion, four hundred sixty-three sextillion, four hundred sixty-three quintillion, three hundred seventy-four quadrillion, six hundred seven trillion, four hundred thirty-one billion, seven hundred sixty-eight million, two hundred eleven thousand, four hundred fifty-six unique IPv6 addresses.

So looks like the boffins brown cord trousers will be safe for a while then.