Base, the layer-2 network developed by Coinbase, plans to upgrade its mainnet with the Denim release. The update aims to reduce block production time to 200 milliseconds, resulting in five blocks per second. This represents a significant increase from the current two-second block interval.
The Denim upgrade is scheduled for activation in November 2026, though this date remains a target. The change will increase daily block production to 432,000. The update was already deployed on the Base Sepolia testnet on October 21, 2026.
Denim replaces the existing Flashblocks mechanism, which provided transaction preconfirmations since July 2025. With the new update, blocks will be settled directly on the chain at high speeds. Developers will need to migrate applications from Flashblocks to the new canonical block and RPC feeds.
The increased block rate is expected to raise RPC call volume and newHeads event notifications by approximately tenfold. Jesse Pollak, the lead developer of Base, noted that Denim is part of a series of performance-focused upgrades following the Azul and Cobalt releases.
