Ampleforth is a decentralised finance protocol designed to support a resilient digital monetary system through a set of modular components. It introduces an alternative approach to building foundational financial tools by separating the role of a unit of account from the role of a store of value. The protocol includes multiple interoperable components, including:

• AMPL, a unit of account token with an elastic supply mechanism
• FORTH, a governance token used to propose and vote on protocol changes
• SPOT, an inflation-resistant token backed by AMPL-based derivatives

Ampleforth’s central idea is to create a stable unit of account that does not rely on centralised collateral or custodians. Instead of stabilising price through reserves or intervention, it adjusts supply algorithmically in response to demand, aiming for a long-run average value that tracks the CPI-adjusted 2019 USD.

This architecture supports a range of decentralised use cases including on-chain lending, borrowing, derivative creation, and decentralised stablecoins without introducing traditional custodial risks.

AMPL is an ERC-20 token that serves as the base unit of account within the Ampleforth ecosystem. Unlike traditional tokens with fixed supply, AMPL implements an elastic supply model in which the quantity of tokens in each user’s wallet automatically increases or decreases once per day based on market demand.

The token’s price targets the 2019 USD adjusted for inflation, but the protocol does not intervene in markets to achieve this. Instead, it proportionally rebases token balances across all holders when the price deviates from the target, allowing the price to gradually return to equilibrium over time.

AMPL is fully decentralised, algorithmic, and non-custodial. It does not require collateral, market makers, or central parties to maintain its price stability properties.

AMPL is primarily used to denominate stable contracts on-chain in a decentralised way. Its unique supply mechanism makes it suitable for:

• Decentralised Lending and Borrowing: AMPL enables long-term loans with more predictable repayment terms compared to floating-price tokens like ETH. Borrowers can repay in AMPL with less exposure to unit price volatility.

• Creation of On-chain Derivatives: AMPL can be used to construct financial products that distribute supply volatility into distinct tranches, such as senior and junior derivative tokens, without oracle risk.

• Collateral for Decentralised Stablecoins: Tranches created from AMPL derivatives can serve as robust on-chain collateral to issue decentralised stablecoins that do not rely on assets like USDC.

• Value Transfer: AMPL can be used as a medium for transferring value with stable long-term purchasing power, particularly in contexts where oracles are a risk factor or cost constraint.

AMPL's rebasing design allows it to act as a foundational primitive for decentralised financial instruments without the constraints of collateralisation or interventionist monetary policy.

Ampleforth was co-founded in 2018 by Evan Kuo and Brandon Iles. Evan Kuo is an engineer with a background in robotics and machine learning, and holds a degree in mechatronics and mechanical engineering from UC Berkeley. Brandon Iles previously worked as an engineer at Google and was one of the early team members at Coinbase.

The project was originally named Fragments before being renamed to Ampleforth. Its initial development was led by Ampleforth Labs, and governance has since transitioned to the FORTH DAO, which is responsible for managing treasury assets, overseeing development, and guiding the protocol's evolution through community governance.