Slowest Blocks

The gap is measured in seconds between a block's timestamp and the timestamp of the block immediately before it. The page lists the top 100 blocks by this inter-block gap, longest first.

Every block in the top 100 was mined within Bitcoin's first year of existence — between the genesis block on 3 January 2009 and early January 2010. This is not a coincidence. In those early months the entire network consisted of a handful of CPU miners, most of the time just one: Satoshi Nakamoto. Without a community of competing miners constantly searching for the next block, hours could pass between blocks. On a modern network mining millions of trillions of hashes per second, a gap of more than an hour is exceptional — the slowest block in the last year had a gap of – (Block –, –). In Bitcoin's first year, it happened regularly.

The longest gap of all — between block 0 and block 1 — stands at 5 days, 8 hours, 39 minutes and 20 seconds. This gap likely reflects not a testing period, but the time it took Satoshi to mine the genesis block itself. The genesis block's hash — 0000000000…b60a8ce26f⧉ — has a Max Equivalent Difficulty of 2,536, meaning its hash required roughly 2,536 times more computational work than the minimum needed at difficulty 1. For comparison, blocks mined in the same week typically had values between 1 and 15. At the hash rate of a typical 2008 CPU (roughly 4 MH/s), finding a hash this far below the target would take, on average, approximately 6 days of continuous mining. Satoshi set the block's timestamp to 3 January 2009 — the date of the Times headline he embedded as proof-of-time: "Chancellor on brink of second bailout for banks." He announced Bitcoin v0.1 publicly on the Cryptography Mailing List on 8 January 2009, and block 1 was mined the next day. Those five days were not idle — the genesis block was being forged. This is supported by the Bitcoin Wiki's "mining duration" hypothesis and the Satoshi Nakamoto Institute's email archive.