Impermanent Loss Calculator

Estimate the impermanent loss of a liquidity pool position. Enter start and current prices of two tokens and compare LP value with holding.

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Impermanent loss
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LP value change vs holding
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Price ratio change
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Impermanent loss is the relative value of an LP position versus holding the two tokens separately. It is not a real loss until you exit.

What Is Impermanent Loss?

When you add liquidity to a constant-product pool (50/50 weight), the pool automatically rebalances as prices move — buying the token that got cheaper and selling the one that got more expensive. If the two tokens no longer have the same relative price as when you entered, your share of the pool is worth less than the tokens you could have simply held. That gap is the impermanent loss, and it is always a percentage between −50% (one token goes to zero) and 0% (no relative price change).

Where the loss comes from
The pool's invariant (price A × quantity A = price B × quantity B) forces the token mix to shift whenever the price ratio changes. Your LP share ends up overweighted in the weaker token. The classic formula for a 50/50 pool is IL% = 2√(x·y) / (x + y) − 1, where x and y are the price changes of the two tokens — so IL depends only on the relative price movement, never on how much both tokens move together.
Why IL = 0 when prices don't move
Set x = y (both tokens move by the same factor, or neither moves) and the formula collapses to 0: 2√(x·x) / (x + x) − 1 = 2x / 2x − 1 = 0. A market where everything rises or falls in lock step creates no impermanent loss; only the change in the ratio between the two tokens does.
When LP revenue covers the IL
Every swap through the pool earns you a fee share (often ~0.05–0.30%), plus any token emissions. If you exit when cumulative rewards exceed the IL at that moment, the net position is profitable. High trading volume + low price volatility is the sweet spot; in volatile pairs the IL typically grows faster than fees can accumulate, so exiting near the original price ratio matters most.

Frequently Asked Questions

What is impermanent loss?

Impermanent loss is the difference in value between providing liquidity in a 50/50 pool and simply holding the same two tokens. When one token's price moves relative to the other, the pool automatically rebalances toward the cheaper token, so your LP position is worth less than the holdings it was made from — until prices return to their original ratio.

Why is impermanent loss zero when prices don't change?

The IL formula is IL% = 2√(x·y) / (x + y) − 1, where x and y are the price changes of the two tokens. If neither price moves (x = y = 1), the formula gives exactly 0. Loss only appears when the relative price between the two tokens changes, and it depends only on that ratio — not on how much both tokens rise or fall together.

When do LP rewards cover the impermanent loss?

Traders pay fees (and sometimes emission rewards) on every swap that passes through the pool. If the cumulative fees you earn exceed the IL at the moment you exit, your net result is positive. This works best in high-volume pairs with low volatility; in volatile pairs the IL usually grows faster than fees accumulate.

Is impermanent loss a real loss?

It becomes real when you withdraw. While you stay in the pool, the difference is only a paper loss versus the hypothetical holding strategy — and it can 'heal' back toward zero if the two tokens return to their original price ratio. The word 'impermanent' describes exactly this: it's permanent only at the moment you exit.

Is my data sent to a server?

No. Every number is computed locally in your browser with JavaScript. The page works fully offline once loaded, and nothing you enter is stored or transmitted.