Quick Slots, block interval from 12 seconds to 10 seconds

Strawmap Hegotá (2027) · quick slots

This proposal turns the interval at which blocks are produced (the slot time) from a fixed value hardcoded in the code into an adjustable setting, and uses that mechanism to shorten the interval from 12 seconds to 10 seconds.

Why it is needed

Today Ethereum produces one block every 12 seconds. Every time you send funds, deposit to an exchange, or make a payment, you feel those 12 seconds directly. A shorter interval improves several things. The loss that liquidity providers on decentralized exchanges (DEX) suffer from arbitrage is proportional to the square root of the block interval. Cutting it to 10 seconds reduces it by about 9%. The time to finality comes sooner, and more block proposers fit in the same period of time, which makes censoring transactions harder. Preconfirmation mechanisms built to mask the 12-second delay become less necessary, and the time L2s wait for several L1 blocks to process deposits also gets shorter. However, the real bottleneck is not the number. The assumption that a slot is 12 seconds is embedded throughout consensus clients and execution clients. This proposal first removes that assumption to make the slot time a setting, and then shortens it conservatively to 10 seconds. It was moved to Considered for Inclusion (CFI) for Hegotá at ACDC #188 in October 2026, but the actual cut to 10 seconds still has to go through further verification. For heze-devnet-2, it was decided to include only the feature and keep 12 seconds. Its inclusion in Hegotá is the Strawmap's estimate, not a commitment.

How it works

  1. Turn slot time into a schedule The hardcoded 12-second constant is removed and replaced with a schedule that lists, from which epoch (a bundle of 32 slots), how many milliseconds a slot lasts. The first entry is the 12 seconds at genesis, and later entries can be added only at network upgrade points.
  2. Add a 10-second entry at the fork A 10-second entry is added to the mainnet schedule from the fork epoch. The mapping between time and slot number is also obtained not by multiplying by 12 seconds from genesis but from a piecewise timetable in which each era's own slot time is joined end to end.
  3. Rewards and penalties are adjusted to real time The consensus constant values stay the same, and the base reward per epoch and the activation and exit limits are scaled by 5/6, and the inactivity penalty by its square. An epoch becomes about 5.3 minutes, and finality shortens from about 13 minutes to about 10.7 minutes.
  4. Gas limit and blob count are reduced too At ACDC #184 in August 2026, it was decided to reduce the per-block gas limit and blob count in proportion to the shorter slot, so that throughput per second stays the same. Changes to other values such as issuance are handled in a separate EIP.

Related EIPs

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