Break-even time of buying miners can be calculated according to miners price, daily mining earnings and daily mining costs. But this is just a static break-even evaluation since diff increase, block reward decrease and mining cost increase may all lead to longer time for break-even.
1. Calculate static daily mining profit
Users can click the following URL to calculate daily profit. This is based on current diff and block reward. The actual profit may change if diff and block reward change.
2. Calculate daily mining cost
If a miner's power consumption is 800W, electricity fee is USD 0.1/KWH, and miner management fee is USD 0.2/day, then your static mining cost is:
Explanation: Divided 800W by 1000, you will get the power consumption in KW, and then time 0.1/KWH and 24 hours. Now you've got the electricity cost. Add miner management fee and maybe other fees and then you will get your daily cost.
3. Calculate break-even time
Miner price/ (daily mining profit-daily mining cost)= days you will spend to reach break-even point