Base ERC-20

Add Liquidity on Base

Deepen a Uniswap pool that already exists on Base. This adds to the v3 or v4 position you already own instead of minting a second one alongside it, which takes roughly half the gas, and it handles v2 pairs the same way. Enter one amount and the pool decides the other. 0.002 ETH.

0.002 ETH service fee plus network gas

How to Add Liquidity on Base

Find the pool

Give it a token address and the Uniswap markets for that token on Base are listed, version by version, or supply a pool address directly if you already know the one you want. Anything your wallet holds appears alongside them.

Decide: top up, or start a second position

Adding to one you already hold leaves its bounds untouched and takes about half the gas. Opening a separate position in the same pool is how you get different bounds. A v2 pair has no ranges at all, so the question does not arise there.

Enter one amount

Type either side and the other is derived from the pool's current price and, on a concentrated position, from where that price sits between your bounds. Only what the ratio needs is taken.

Sign for the approval, do not pay for it

Where a token implements permit, the allowance becomes a signature that costs nothing, and Permit2 handles a good share of the tokens that do not. Only a token supporting neither forces a real approval transaction, and you are warned up front when that applies.

Check the dry run, then confirm

The deposit is rehearsed against Base as it stands right now, so you see exactly what leaves your wallet and what liquidity you get for it, and it names the reason in plain words if the deposit would not go through.

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No Code Required

Create and launch tokens without writing any code. Visual configuration for all features.

visibility

Fully Transparent

All token data is publicly visible and verifiable on block explorers.

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Multi-Chain

Available on Solana, Ethereum, Base, Arbitrum, Polygon, and BNB Chain.

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Full Ownership

You have full control. We never hold your keys, tokens, or authority.

Frequently Asked Questions

Start from the token address, or the pool address if you already have it, and pick the market you want out of what comes back. Where you already hold a position in that pool, select it and the money goes into that one instead of creating another beside it. Then supply either of the two amounts and the pool settles the second. Sign the approval where the token permits it, look over the dry run, and confirm. This works on Uniswap v2 pairs and on v3 and v4 pools across Base, against ETH or Circle's native USDC.

Yes, and this is the main reason to use this rather than something else. Every comparable tool we could find mints a brand new position NFT each time you deposit, even when you are adding at exactly the same price range, so a wallet that deposits three times ends up managing three separate positions instead of one. Uniswap's own app does support topping up, so we are not claiming to be the only route, only that among the third-party tools this is the one that does not fragment your liquidity.

Noticeably, yes, and the gap is structural rather than a fee we set. Measured against real Base transactions, increasing an existing v3 position runs about 221,000 gas while minting a fresh one runs about 437,000. Topping up is roughly half the work because the position already exists and its ticks are already initialised. On Base both numbers are small in absolute terms, but the ratio holds everywhere and it compounds if you add regularly.

No, and the distinction is worth stating carefully because writing on this subject gets it wrong in both directions. Adding to a position you already own is entirely possible; handing that position new bounds is not. Its ticks are read straight out of storage and there is no parameter for supplying different ones. So a top-up expresses more conviction at the range you originally chose, and changing your mind about the range means minting a separate position instead.

Seven, which is worth knowing because almost everything published says four. Alongside the usual 0.01%, 0.05%, 0.30% and 1.00%, Uniswap governance switched on 0.02%, 0.03% and 0.04% here in September 2024, with tick spacings of 4, 6 and 8 respectively. Base is the only chain we support where this is true, and Uniswap's own help pages still describe four. The practical consequence is that a pair you assume sits on 0.05% may actually be trading on 0.03%, which is a different pool with different depth and a different price, and all seven are searched when you paste a token address here.

That depends on the version, and the two do opposite things. v3 leaves them alone: what you have earned moves to your claimable balance and the full figure you typed comes out of your wallet regardless. v4 spends them, putting the earnings toward the deposit before touching your balance, so you part with less than the number on screen. Nothing in the interface signals which one you are about to get, which is why the dry run shows the real amount before you sign anything.

Not for a v4 pool, which handles native ETH directly and treats it as a first-class asset rather than something to be wrapped. On v2 and v3 the pool holds wrapped ETH, so a deposit passes through WETH, though that happens inside the same transaction here rather than being something you do separately first.

A v2 pair takes both sides at whatever ratio its reserves happen to sit at, handing back LP tokens for your share of that liquidity pool. Concentrated liquidity varies with where the price falls between your bounds: roughly balanced in the middle, tilting further toward one asset the nearer the price gets to an edge, and entirely one asset once it has passed one, at which point a top-up needs only that token. The second figure is quoted live while you type, since guessing at a fifty-fifty split is wrong more often than not on a concentrated position.

Either works, and this tool quotes against ETH or Circle's native USDC. One thing to know if you are joining an older pool: Base ran on a bridged dollar, USDbC, before Circle issued natively, and that legacy token is still around at a different address. Circle does not issue or redeem it, and liquidity against it has thinned to a small fraction of the native token's. Depositing into a USDbC pool means committing capital to a market that is quietly emptying, so check which dollar a pool actually holds before joining it.

No, and on a concentrated position it is not even mechanically possible: the liquidity is placed at the ticks you nominated, and the slot holding the pool's price is never written to. A v2 deposit made at the prevailing ratio grows both reserves in proportion, which by definition leaves that ratio, and so the price, exactly where it started. What your deposit does alter is how far a later trade can push the price, which is close to the opposite of what people worry about.

Not execution price, since nothing is being swapped here. In the gap between building the transaction and mining it, a trade by somebody else can tilt the pool, and the pair of figures you agreed to stops being the pair the pool will accept. Your tolerance sets how much tilt is allowed before the deposit reverts instead of silently going in at proportions you did not choose. The penalty for hitting it is a wasted gas fee, never your principal.

Yes, any Uniswap pool on Base regardless of who opened it or where the token came from. The thing to check first is that the pool's price roughly matches where the asset trades elsewhere. Depositing into a pool that has drifted hands the difference to whoever arbitrages it back, and Uniswap's own warning about this describes the possible outcome as full and permanent loss of funds. It takes half a minute to compare and it is the one genuine danger in joining a market you did not make.

0.002 ETH plus gas, and gas on Base for a top-up is a small fraction of a cent at current prices. Published fees across comparable tools run from 0.001 ETH to 0.015 ETH, and several publish nothing at all, so we are not the cheapest here. Going direct through Uniswap costs only gas. What the fee buys is the top-up path, the signature approvals and a dry run before you commit.

Whenever you like, in whatever proportion, unless the position was deliberately burned or locked. Remove liquidity withdraws from 1% to all of it and pays out a concentrated position's earned fees at the same time. If no pool exists yet, the Base pool creator opens one instead.

Topping Up Costs Roughly Half of Starting Over

Most tools in this space, and most guides, treat adding liquidity as a synonym for creating a position. That is a fair description of the first time you do it and a poor one thereafter. Once you have spent a while providing liquidity in a pool, collecting trading fees from every swap that crosses your fee tier, the common thing you want is more of it in the position you already have, and that is a genuinely different operation with a genuinely different price. Reading real Base transactions, increasing an existing v3 position costs around 221,000 gas against roughly 437,000 to mint a new one. The position already exists and its ticks are already initialised, so there is simply less work to do.

The cost is only half the argument. Every third-party tool we examined mints a fresh NFT on each deposit into the same liquidity pool, including when you are adding at exactly the range you already chose, and none of them warn you about it. A liquidity provider who deposits three times ends up managing three positions that should have been one: three sets of fees to collect, three things to close, and three transactions to pay for when you eventually exit. This tool takes the position you already own and adds to it, which is the boring correct behaviour that somehow nobody ships.

Why Your Second Deposit Behaves Differently From Your First

There are two surprises waiting on a top-up, and both come from the fact that the position now has history. The first is that its price range is fixed. The contract reads the bounds out of storage and gives you no way to supply new ones, so a top-up can express more conviction at the range you picked but cannot express a change of mind about that range. If your view has moved, what you want is a second position, and the reason to be deliberate about it is the fragmentation described above rather than the gas.

The second is that the position has been earning, and the two live Uniswap versions disagree about what to do with those earnings. On v3 the fees stay where they are and your wallet pays the full amount you entered. On v4 the uncollected fees are spent as part of the deposit first, so your wallet covers only the shortfall. Ask for the same amount on each and a different number leaves your account. Neither behaviour is wrong and both are defensible, but they are opposites behind an identical-looking button, which is why the amount in the dry run is the amount that actually moves.

What Base Actually Changes About This

Gas on Base is small enough that it stops driving the decision, and that is worth naming because so much liquidity advice is really gas advice in disguise. On a chain where each transaction is expensive, people batch deposits, avoid concentrated positions and default to whatever is cheapest to deploy. Here you can top up at the moment it is useful rather than at the moment it is affordable, and pick a version because it suits the position rather than because it is the least costly to open.

Uniswap v4 has been live on Base since early 2025 and changes one practical thing for depositors: it treats native ETH as an asset in its own right, so an ETH-paired deposit does not need wrapping at all. On v2 and v3 the pool holds WETH and the wrap happens inside the same transaction here. Combined with permit signatures, which cost nothing, a top-up on Base frequently means one signature and one cheap transaction with no approval to pay for beforehand.