What to Know
- Zcash developers have proposed reducing the target block interval to 20 seconds from 25 seconds.
- The proposal comes just days after the NU7 upgrade reduced Zcash block times from 75 seconds to 25 seconds.
- A 20-second target would mean a first confirmation could arrive in about 20 seconds rather than 25 seconds, while a three-confirmation wait could fall from 75 seconds to 60 seconds.
- Early network data showed an observed orphan rate of 0.69% over the 24 hours ending early Monday, compared with approximately 0.66% before NU7.
- The orphan rate across the entire period since NU7 stood at 1.29%, with readings declining after an initial spike.
- ZecBlock expanded its monitoring network from one node to ten shortly before the upgrade, making exact before-and-after comparisons difficult.
- Developers tested 20-second blocks on a network of 80 miners across 12 regions, with lost competing blocks ranging from 1.9% to 3.3% depending on software used.
- The proposal would preserve daily private transaction capacity, Zcash’s issuance schedule and the 21 million coin supply limit.
- The change has not been approved and has no activation date.
Zcash Developers Look Beyond NU7
Zcash developers are already weighing another speed increase after the network completed a major upgrade that made blocks three times faster. The latest proposal would lower the target time between blocks to 20 seconds from 25 seconds, following the NU7 upgrade that reduced the interval from 75 seconds. The idea is aimed at making ZEC payments feel faster in everyday use while attempting to avoid a disruptive rise in orphaned blocks, a key technical concern for proof-of-work networks that shorten block intervals.
The proposal was outlined Sunday by developers Dev Ojha and Evan Forbes. It arrives only days after the network’s Friday upgrade, underscoring how quickly the Zcash development community is moving to evaluate whether faster confirmations can be achieved safely. Blocks are the ordered batches of transactions added to the blockchain, and a shorter interval means users can receive a first confirmation sooner. For payments, especially point-of-sale transactions or transfers into trading venues, faster confirmations can improve the practical user experience.
Under the proposed adjustment, a customer paying with ZEC at a shop could expect a first confirmation in about 20 seconds rather than 25 seconds. An exchange requiring three confirmations could see the expected wait fall from 75 seconds to 60 seconds. Those estimates remain averages because miners find blocks unpredictably. Even when a network targets a fixed interval, real-world confirmation times vary from block to block due to the probabilistic nature of mining.
Why Orphan Blocks Matter
The central issue for the proposed shift is not simply whether blocks can be produced more frequently, but whether the network can do so without causing miners to waste significantly more work. When two miners discover valid blocks at nearly the same time, the network ultimately accepts one version of the chain and discards the other. The discarded block is known as an orphan. For the miner that produced it, the electricity and computing work behind that block do not lead to a reward.
Faster block times can raise orphan risk because miners have less time to learn that another miner has already found a block. If information about a new block has not propagated across the network before another block is found, competing versions of the chain can briefly emerge. That competition is eventually resolved, but the losing side represents wasted work. A rising orphan rate can also influence mining economics by making revenue less predictable, particularly for miners with slower network connections or less favorable infrastructure.
Early figures after NU7 have encouraged some Zcash developers because the observed orphan rate has stayed close to levels seen before the upgrade, despite blocks arriving much more frequently. Zcash’s observed orphan rate stood at 0.69% over the 24 hours ending early Monday, based on ZecBlock’s mining tracker. That compares with approximately 0.66% before NU7. Ojha said Monday that the orphan rate had improved beyond his expectations.
Still, the data is not a perfect before-and-after comparison. The orphan rate across the entire period since NU7 stood at 1.29%, with readings declining after an initial spike. ZecBlock also expanded its monitoring network from one node to ten shortly before the upgrade. That change means the monitoring system can now detect some competing blocks that previously may have gone unnoticed. As a result, the figures are useful but not definitive when assessing whether the live network is truly producing the same level of discarded mining work as it did before NU7.
Simulations Point to Manageable Risk
Developers also tested the proposed 20-second blocks in a simulated environment designed to measure how often competing blocks would be discarded. The tests used a network of 80 miners spread across 12 regions. Depending on the software used, between 1.9% and 3.3% of competing blocks were lost. Those results compared with 4.68% in earlier stress tests that helped establish whether 25-second blocks were safe.
For technical traders and market participants following ZEC, the simulation results are notable because they suggest that the network may be able to reduce confirmation times again without triggering a sharp increase in wasted mining work. However, simulations do not guarantee live network performance. Real-world conditions can introduce unexpected variables, including differences in miner connectivity, software behavior, node configuration and propagation patterns during periods of heavier activity.
The distinction between a controlled test and mainnet behavior is especially important for a privacy-focused blockchain. Zcash developers are attempting to balance speed, miner incentives and wallet performance while preserving core monetary parameters. Faster confirmation times may make payments more convenient, but the network must also avoid placing unnecessary strain on participants that maintain infrastructure or use wallets to process private transactions.
Private Capacity and Supply Would Be Preserved
The proposed change is not designed to increase how many private transactions Zcash can handle each day. Developers plan to allow fewer transactions per block to offset the fact that more blocks would be produced. That approach is intended to prevent wallets from having to process additional data simply because the chain is creating blocks more often. In other words, the proposal is about reducing confirmation latency rather than expanding daily transaction throughput.
The plan would also preserve Zcash’s issuance schedule and its 21 million coin supply limit. That detail matters for market participants because changes to block frequency can sometimes raise questions about whether coins are being created faster. In this case, the proposal is framed to keep issuance aligned with the existing monetary schedule, despite the shorter target interval between blocks.
Maintaining the 21 million coin supply limit also helps keep the proposed upgrade focused on usability rather than monetary redesign. Zcash has long combined proof-of-work mining with optional privacy features, and any adjustment that touches block timing must be evaluated through multiple lenses: user experience, miner economics, node performance, wallet burden and monetary consistency. The latest proposal attempts to move one of those levers without changing the others.
Approval Is Still Pending
Despite the encouraging early data, the 20-second block plan remains a proposal. It has not been approved, and no activation date has been assigned. Ojha and Forbes want the change considered in the next community poll and potentially included in NU7.1, a future network upgrade. That means the Zcash community still has to evaluate the data, debate trade-offs and decide whether the additional speed is worth adopting so soon after NU7.
The timing is notable. Moving from 75 seconds to 25 seconds was already a major change for Zcash’s payment experience. A further move to 20 seconds would be a smaller step in absolute terms, but it would still require confidence that the network can absorb the shift. The fact that developers are discussing another reduction so quickly suggests that early NU7 performance has eased some concerns, but it does not eliminate the need for continued monitoring.
For users, the practical appeal is straightforward: faster first confirmations can make payments feel more responsive. For exchanges, a shorter expected wait for three confirmations may improve deposit handling, though each platform sets its own policies. For miners, the main concern remains whether orphan risk rises enough to affect rewards. For developers, the challenge is to interpret data that is promising but complicated by monitoring changes and the short period since the upgrade.
FXCOINZ will be watching whether the proposal advances through community review and whether post-NU7 orphan-rate data continues to stabilize. If the network can maintain acceptable orphan levels while shortening block intervals again, Zcash could take another step toward quicker payment confirmation times. If live metrics worsen, however, developers may face pressure to slow the pace of changes or gather more data before moving ahead.
Frequently Asked Questions (FAQs)
What is Zcash proposing now?
Zcash developers are proposing a reduction in the target time between blocks to 20 seconds from 25 seconds. The change is intended to make payment confirmations arrive sooner while preserving core network parameters.
How recently did Zcash speed up its blocks?
Zcash completed the NU7 upgrade just days before the new proposal was outlined. NU7 reduced the block interval from 75 seconds to 25 seconds, making blocks arrive three times faster than before.
How would 20-second blocks affect confirmation times?
A first confirmation could be expected in about 20 seconds rather than 25 seconds. For an exchange requiring three confirmations, the expected wait could fall from 75 seconds to 60 seconds, though actual times vary because mining is unpredictable.
What is an orphan block?
An orphan block is a valid block that is ultimately discarded when the network chooses a competing block instead. This can happen when miners find blocks at nearly the same time, leaving one miner with work that earns no reward.
What did early NU7 data show?
Zcash’s observed orphan rate was 0.69% over the 24 hours ending early Monday, compared with approximately 0.66% before NU7. Across the entire period since NU7, the rate was 1.29%, with readings declining after an initial spike.
Why are the orphan-rate comparisons imperfect?
ZecBlock expanded its monitoring network from one node to ten shortly before the upgrade. Because the expanded system can detect some competing blocks that previously may have gone unnoticed, the figures cannot provide an exact before-and-after comparison.
What did developer simulations find?
Developers tested 20-second blocks on a network of 80 miners across 12 regions. Depending on the software used, between 1.9% and 3.3% of competing blocks were lost, compared with 4.68% in earlier stress tests tied to 25-second blocks.
Would the change increase Zcash’s daily private transaction capacity?
No. Developers plan to allow fewer transactions per block to offset the higher number of blocks, so daily private transaction capacity would be preserved and wallets would not have to process extra data.
Has the 20-second block plan been approved?
No. The proposal has not been approved and has no activation date. Developers want it considered in the next community poll and potentially included in NU7.1, a future network upgrade.