Zcash developers have proposed cutting the network's target block spacing from 25 seconds to 20 seconds, aiming to deliver faster first confirmations without increasing daily issuance or shielded transaction capacity. The proposal was published in a community forum by developers ValarDragon and Evan Forbes and is intended for inclusion in the next poll and the upcoming NU7.1 upgrade.
The change builds on the NU7 mainnet activation, which reduced target block spacing from 75 seconds to 25 seconds. According to developers, transactions can still wait for block inclusion when blocks have spare capacity, creating friction for point-of-sale payments, exchange deposits, withdrawals and cross-chain swaps. Cutting another five seconds would shorten time to first confirmation and improve back-to-back payment latency.
Stress tests used an 80-miner network across 12 regions with full 2 MB blocks. A Zakura-only network produced a 1.9% orphan rate, while a 50-50 Zakura and Zebra-Andele setup reached 3.3%. Both results meet or improve upon the readiness bar previously used for 25-second blocks, where testing showed a 4.68% empirical orphan rate and a 3.26% theoretical estimate. Developers attributed the improvement to work in Zakura and Zebra-Andele, building on Zebra performance and security upgrades.
The proposal would scale shielded action limits by four-fifths rather than allowing faster blocks to increase daily private-transaction capacity. Orchard and Ironwood actions per block would fall from 330 to 264, while Sapling inputs plus outputs would drop from 300 to 240. Keeping daily shielded maxima unchanged is intended to prevent a 25% increase in worst-case light-wallet synchronization load. The 2 MB block-size limit would remain unchanged, separating latency improvements from future throughput expansion.
Monetary and timing parameters would also be adjusted to preserve wall-clock behavior. Per-block issuance would fall proportionally, while the halving interval would expand from 5.04 million to 6.3 million blocks. Default transaction expiry, difficulty averaging and reorganization-related settings would scale. The proposal changes block frequency without altering expected daily issuance or asking services to reduce confirmation counts.
Meanwhile, ZEC faced selling pressure, falling 3.80% to $1,215 in 24 hours and underperforming Bitcoin, which dropped 2.02% over the same period. The next step for the block-time proposal is governance consideration as Zcash continues its community-backed push for faster transactions.
