Nearly 4 Million Bitcoins Lost Forever, New Study Says

Just as gold bars are lost at sea or $100 bills can burn, bitcoins can disappear from the Internet forever. When all 21 million bitcoins are mined by the year 2040, the actual amount available to trade or spend will be significantly lower.

According to new research from Chainalysis, a digital forensics firm that studies the bitcoin blockchain, 3.79 million bitcoins are already gone for good based on a high estimate—and 2.78 million based on a low one. Those numbers imply 17% to 23% of existing bitcoins, which are today worth around $8,500 each, are lost.