Groestlcoin

Groestlcoin is a proof-of-work coin launched in March 2014 that hashes with two rounds of Grostl-512, one of the five finalists in the NIST hash competition and built on the same S-box structure as AES. Blocks arrive about once a minute, the subsidy halves every 10,080 blocks down to a fixed 5 coins, and supply is capped at 105 million; the UTXO model matches bitcoin, so improvements from Bitcoin Core port cheaply. It was the first chain to activate SegWit in January 2017, enabled Taproot ahead of bitcoin, and completed a mainnet Lightning transaction.

The ecosystem keeps a broad wallet matrix with official or community builds for desktop, mobile, browser and hardware, merchant acceptance through a Groestlcoin build of BTCPay Server, and atomic swaps that exchange directly with other UTXO chains. In December 2025 the core wallet was brought in line with the then-current bitcoin reference implementation, continuing its practice of tracking upstream. Consensus combines Groestl-512 with double SHA-256, SegWit and Taproot widen script flexibility, and Lightning nodes carry small instant settlements.