What is KatKoyn ?

KatKoyn is a cryptocurrency which was launched as Nyancoin in January 2014. The original announcement was on bitcointalk.org

Unfortunately, the original developers mysteriously disappeared a couple of months later, without any reason or explanation. It's rumoured that they turned into Doges. Or something.

The original website and other services ceased working shortly after that - however all was not lost, since enough people kept the software running and continued to mine the coin.

In January 2023, 9 years after the original launch, the owner of certain rainbow cat related artwork requested that it be removed, and hence Nyancoin became KatKoyn.


The current software is based on Litecoin, which itself is derived from Bitcoin.

Proof of work, Scrypt algorithm
337 000 000 Coins (see below)
337 coins per block
1 Minute Blocks
P2P port: 33701
RPC port: 33700 (default, can be changed in configuration options)
Subsidy halves in 500k blocks
Difficulty Retarget Time: 3 hours
1% premine

Coins per block

estimates of KatKoyn mining per year First 49 blocks (1-49): 67400. (Intended to be the 1% premine, 50*67400 = 3370000, but actually only 49*67400)

337 from block 50, mined 6 January 2014.
168.5 from block 500000 mined 28 December 2014.
84.25 from block 1000000 mined 25 December 2015.
42.125 from block 1500000 mined 28 December 2016.
21.0625 from block 2000000 mined 22 December 2017.
10.53125 from block 2500000 mined 06 December 2018.
5.265625 from block 3000000 mined 28 November 2019.
2.6328125 from block 3500000 mined 30 November 2020.
1.31640625 from block 4000000 mined 27 November 2021.
0.65820312 from block 4500000 mined 20 November 2022.

Originally, the specifications were to halve the coins every 337k blocks, this was changed after just a few weeks to 500k. Unfortunately, plenty of other sites still list the incorrect 337k.

The total amount of KatKoyn was intended to be 337 000 000, however due to an error by the original developers, the actual total is more, as the block rewards will continue halving until they reach zero.

Total theoretical amount is approximately 340 285 749 - in reality is will be less as many blocks exist with smaller than the maximum generation amount.

The image shows an approximate prediction for the total amount of KatKoyn, this assumes that decimals beyond 8 places are truncated, and that each 500k blocks takes one year.

500k blocks should take 500000 minutes, and a year is longer at 525600 minutes, however block times vary depending on mining activity and other factors. The text list above shows actual block rewards to date.

Halving will continue until approximately the year 2049 when rewards will be zero.

The 'other' nyancoin

When launched in 2014, some other group had also created a Nyancoin, however theirs had a 10% premine for maximum greed, didn't work properly (or at all) and generally was not welcomed by anyone. They then changed their coin name to CRD and shortly afterwards disappeared as well. Now let's never speak of them again.

Possible network split in 2014

There is some evidence to suggest a network split or fork of some kind in 2014, which would have resulted in transactions and mined KatKoyn apparently disappearing without trace. Details on reddit here and also here.

Due to how the network operates, any evidence of this would have been automatically deleted once clients agreed on the chain which is currently in use, leaving only the 'missing' transactions within old copies of various wallets.

Exactly how or when this happened is not known, and will probably never be known. The most likely explanation is due to very small numbers of nodes with little or no communication between them - at the time, the DNS seed for the software was not working and starting a new instance of the client software would have to rely entirely on nodes being added manually.

Rumours and misinformation about X11 and POS

Certain individuals proclaimed in April 2014 that KatKoyn would be switching from Scrypt to X11. This did not happen.

Others decided in early 2015 that it would be a splendid idea to change to a proof-of-stake model instead of the current proof-of-work one. This did not happen either.

KatKoyn is proof-of-work / POW and uses Scrypt, just like it has since it started in January 2014.

Why addresses start with K...

The source code indicates that the original intent was for addresses to start with N...

    PUBKEY_ADDRESS = 45, //N

as can be seen above with the line ending in //N - the number is what defines the start of the address, N is just a comment or note.

However the numeric code entered there (45) is for the letter K, which is why all addresses start K...

It's not clear how such a blunder could be made, as the correct number for N is 53 - an entirely different number, and not one that could be confused for 45, or even easily typed on a keyboard instead of 45.

The other lines there are identical to Bitcoin - script addresses which start with 3..., and two types of addresses for a test network which would start with m... or n... for PUBKEY_ADDRESS_TEST, and 2... for SCRIPT_ADDRESS_TEST.

As of January 2023, these K... addresses are a perfect fit for the new KatKoyn name.

Updated 28 January 2023. Contact / impressum