Crypto Gloss

Impermanent Loss

Impermanent loss (IL) is the difference in value between providing liquidity to an AMM liquidity pool and simply holding the same tokens in your wallet — it occurs because the AMM rebalances your position as prices change. It’s called “impermanent” because the loss only becomes permanent when you withdraw; if prices return to their original ratio, the loss disappears.

How It Works

When you deposit tokens into a liquidity pool, the AMM’s smart contract constantly rebalances your position to maintain its pricing formula. If one token rises in price, the pool sells some of it and buys more of the other — meaning you end up holding more of the token that dropped and less of the one that pumped.

Here’s the key insight: the pool always sells your winners and buys your losers, which is the opposite of what a HODLer experiences.

The Math (Simplified)

For a standard 50/50 constant product pool (x × y = k), impermanent loss depends only on the price ratio change between the two tokens:

Price Change Impermanent Loss
1.25x (25% up) 0.6%
1.5x (50% up) 2.0%
2x (100% up) 5.7%
3x (200% up) 13.4%
4x (300% up) 20.0%
5x (400% up) 25.5%

The formula: IL = 2 × √(price_ratio) / (1 + price_ratio) − 1

This means if ETH doubles in price relative to USDC, you’d have 5.7% less value than if you’d just held both tokens. The loss is symmetrical — it doesn’t matter which direction the price moves, only the magnitude of the ratio change.

Worked Example

You deposit into an ETH/USDC pool when ETH = $2,000:

  • Deposit: 1 ETH + 2,000 USDC (total value: $4,000)
  • ETH doubles to $4,000
  • If you just held: 1 ETH ($4,000) + 2,000 USDC = $6,000
  • Pool rebalances to: ~0.707 ETH ($2,828) + ~2,828 USDC = $5,656
  • Impermanent loss: $6,000 − $5,656 = $344 (5.7%)

You still made money ($5,656 vs your original $4,000), but you’d have made more by just holding. That’s impermanent loss.

When It Becomes Permanent

Impermanent loss becomes permanent when you:

  • Withdraw from the pool at a different price ratio than when you entered
  • The token goes to zero — no chance of the ratio reverting
  • The pool is exploited and liquidity is drained

Mitigation Strategies

  • Correlated pairs — Pools with tokens that move together (e.g., stETH/ETH, USDC/USDT) experience minimal IL because the price ratio barely changes
  • Higher-fee pools — A pool earning 1% daily in fees can easily offset 5% IL over a week
  • Wider ranges (Uniswap V3) — Wider concentrated liquidity ranges reduce IL but also reduce fee concentration
  • Single-sided staking — Some protocols (Bancor V3, Thorchain) offered IL protection, though Bancor paused this feature in 2022
  • Short timeframes — LP during low-volatility periods and withdraw before major price swings

History

  • 2018 — The term “impermanent loss” is coined within the Bancor community. Early AMM users begin documenting the phenomenon as Uniswap V1 gains traction.
  • 2020 — DeFi Summer makes impermanent loss a mainstream concept as millions of users provide liquidity for the first time. Pintail’s blog post “Uniswap: A Good Deal for Liquidity Providers?” introduces the IL formula to a wide audience.
  • 2020 — Bancor V2 introduces an impermanent loss protection mechanism, promising full IL coverage after 100 days of staking.
  • 2021 — Uniswap V3’s concentrated liquidity amplifies impermanent loss for LPs who set narrow ranges. Research papers show that over 50% of Uniswap V3 LPs underperform simply holding.
  • 2022 — Bancor pauses its IL protection program after $26 million in losses, demonstrating that IL protection is extremely difficult to sustain at scale.
  • 2023 — Academic and on-chain analysis confirms that the majority of LPs on standard AMMs lose money to impermanent loss net of fees, especially on volatile pairs.
  • 2024 — “Loss-vs-rebalancing” (LVR) emerges as a more precise framework for understanding LP losses, accounting for arbitrage extraction alongside classical IL.
  • 2025 — New AMM designs incorporating oracle-based pricing and dynamic fees aim to reduce IL for passive LPs.

Common Misconceptions

  • “Impermanent loss means I’m losing money.”

Not necessarily. You’re losing money relative to holding. If you deposited $4,000 and your position is worth $5,000 with 5% IL, you still profited $1,000 — just less than you would have without the pool.

  • “IL only happens when prices drop.”

IL occurs with any price ratio change — up or down. A 2x price increase causes the exact same IL as a 2x decrease. It’s the magnitude of divergence that matters, not the direction.

  • “Stablecoin pools don’t have impermanent loss.”

Stablecoin pools have minimal IL because the price ratio stays close to 1:1, but it’s not zero. During the USDC depeg in March 2023, stablecoin LPs experienced meaningful IL.

Criticisms

  1. Misleading name — “Impermanent” implies the loss reverses easily, but in practice many positions never return to their original price ratio. “Divergence loss” is a more honest term.
  2. Hidden complexity — Most DeFi users providing liquidity don’t understand IL math, leading to unexpected losses.
  3. Protocol incentive alignment — Protocols want deep liquidity and downplay IL risk when advertising yield farming APYs that may not cover the actual loss.
  4. Unsolved problem — Despite years of research and experimentation, no AMM design has eliminated IL without introducing other trade-offs (oracle dependence, reduced capital efficiency).
  5. Net-negative for retail — Studies consistently show that unsophisticated LPs lose more to IL than they earn in fees, subsidizing arbitrageurs.

Social Media Sentiment

Impermanent loss is one of the most discussed and debated topics on r/defi and r/UniSwap. Beginners frequently ask “is providing liquidity worth it?” and experienced LPs share strategies for managing IL. On r/CryptoCurrency, IL is often cited as the reason DeFi is “for degens only.” Crypto Twitter debates rage over whether concentrated liquidity makes IL worse and whether new AMM designs can solve the problem.

Last updated: 2026-04

Related Terms

Sources

  • Angeris, G., & Chitra, T. (2020). “Improved Price Oracles: Constant Function Market Makers.” Proceedings of the 2nd ACM Conference on Advances in Financial Technologies (AFT ’20).
  • Pintail. (2019). “Uniswap: A Good Deal for Liquidity Providers?” Medium.
  • Milionis, J., Moallemi, C. C., Roughgarden, T., & Zhang, A. L. (2022). “Automated Market Making and Loss-Versus-Rebalancing.” arXiv preprint arXiv:2208.06046.