how much would it cost to carry out an 51%-Attack? If there is a place service in the web that you can rent ASIC's than i would rather hear what renting this would cost. If not then buying the asics is fine too.
To keep the calculation KiSS following assumptions:
- Attacker chooses the cheapest way of renting/buying hardware. But he is NOT renting/bribing whatever the existing machines from miners from the existing bitcoin network. The gear has to come from outside the network.
- Don't worry about that renting/buying such a huge qt would drive the price for the hardware up.
- Ignore what the community would do, the cored devs or whoever to counterstrike your attack.
- you don't need to include electricity cost in the calculation. If you do include it, please tell what you took for US-Cents/kw/h
P.S. is there a website that does this calculations on a regular basis? Would be cool to check this from time to time..
Update 4 Years later ond June 2019: The Hashrate of the Entire Network is right now (according to Bitinfocharts.com): 55,42 ExaHashes. Most efficient Miner is the DragonMint which has exactly (and realisticaly) 16 TH/s and costs including with power supply 2844USD. One would need 55 420 000 TH/s /16 TH/s =3,46 millin Dragon Mints * ~ 2800USD (included a small rebate)~ 9,8 billion USD. Crazy how the cost increased in the last 4 years from 145 Million to almost 10 billion...
EDIT X Years old answers to this question don't matter at all. This question needs to answered every 6 months. Entirely new generations of Asic-miners, change picture a LOT