Safely and easily trade NFTs with anyone, for free

There's no trading fee (just pay gas), and trades are peer-to-peer, verified and guaranteed by smart contracts on-chain – we use Seaport Protocol. Both parties can review before signing and executing the trade, and trades can be revoked or canceled at any time before execution.

How it works

Sign into with your crypto wallet

This requires a signature to securely authenticate wallet ownership (EIP-4361).

View trades on your wallet dashboard

All trades you create, or that are created by others who want to trade with you, will appear in your dashboard.

Create a new trade

Input a valid ETH wallet address, select tokens from both sides, and sign Seaport messages. Cancel any time until accepted. Expires after 1 week.

Accept or Reject a trade

You can review, accept and sign trades sent to you, or reject them. If either wallet cannot complete the trade (i.e. missing assets), you will be unable to accept the trade until that is resolved.


Currently, the swap service is totally free – you only have to pay for gas when your messages/transactions are deployed on chain.

You may see a "Royalty" fee percentage taken out of swaps that include a liquidity token (like ETH or MATIC) but that is a Creator Royalty calculated for the NFTs included in the swap -- 100% of that fee goes to the creator/artist of the NFT, ampule is totally free to use.
Yes, right now we only support trades on Polygon and Ethereum. This is for a number of reasons, including that we are a small team and the users we've seen needing ampule's "safe swap" tool the most have been trading on Polygon and Ethereum. We plan to add more blockchans in the future!
You only have to pay gas from your wallet when you sign a message for a trade that needs to be deployed on-chain. This happens when:
  1. When you create a trade, the message you sign granting Seaport access to transfer the collections/contracts specified in your trade has to be deployed on-chain. The message containing the actual trade is not deployed until the counterparty signs.
  2. When you receive and execute an open trade created by someone else, you may need to sign multiple messages that need to be deployed (see question below about multiple messages).
  3. If you created a trade and want to cancel it, you may need to pay gas to ensure the trade cannot be executed.
Ampule uses Seaport, a secure, open source blockchain trading protocol created by OpenSea. When a trade is created or executed with Seaport, it works by asking for two types of signatures:
  1. the first grants the Seaport smart contract permission to transfer tokens in your wallet (NFTs or fungible crypto tokens) for a specific token contract or NFT collection; this gets deployed on-chain immediately and requires gas fees
  2. the second Seaport signature contains the details of this specific transaction, what assets you're sending and what you expect to receive in return; this only gets deployed when all parties have signed, so only the last wallet to sign deploys it and pays gas
The first signature allows Seaport to execute future transactions on your behalf using their format for signed messages that define the trades.

If you're an active trader and have already granted Seaport permission to the collections in a transaction, you may only need to sign the second type of message detailing the specific transaction because Seaport already has your permission. Alternatively, if your trade includes assets on multiple chains, you may need to sign more than two messages so they can be deployed on multiple chains.
All NFTs on Ethereum and Polygon are supported natively, though you can only swap assets on one chain at a time. In addition to NFTs, we support Ethereum/Wrapped Ethereum, Polygon's native Matic (and Wrapped Matic) token, as well as some community and staking tokens like BitCone ($CONE), Bapeliens's $SLIME staking token, Gen K's $RISE staking token, etc. Creator royalties are currently collected when any fungible tokens are included in a swap if they are opposite NFTs (see "Does ampule enforce creator royalties?" for more info). While ERC20 tokens can be included on either side of the swap, native tokens like MATIC on Polygon or ETH on Ethereum can only be included on the recipient's side because native tokens do not have the token allowance contract methods required to grant permission to the swap contract -- so if you want to send a token, the other party must create the swap, or if you want to receive a native token, you must create the swap; "wrapped" tokens like WETH and WMATIC were created in part to add these token allowance contract methods, so wrapped tokens can be included on either side of a swap.

We are also open to adding more community tokens, so if your community is using a token and you think they'd want to be able to use it in swaps, feel free to message @MrCrabdad on Twitter/X to get your Polygon or Ethereum ERC20 token added to ampule! Or, if you would like to get your NFT project a "verified" checkmark on ampule, feel free to reach out :)

Because we support ALL NFTs, please always make sure the assets offered by someone else are genuine/authentic, as it is unfortunately easy to create counterfeit NFTs. Fortunately with fungible tokens, because we manually verify and add new tokens manually, you can be confident fungible tokens are always authentic. With that said, being able to swap a token on ampule is NOT an endorsement of the token, we just want users to be able to swap safely and easily. Please always do your own research and make informed decisions.
We very strongly believe creators are entitled to the royalties they set for their creations, and will always enforce royalties when a creator has defined them on-chain. Please note that whenever you see a "Royalties" percentage/fee, 100% of that goes to the artists -- ampule does not charge any platform/trading fees and is entirely free to use. We check for creator royalties using Royalty Registry, which aggregates a number of different royalty standards like EIP-2981, Manifold, Rarible, and SuperRare. As long as a creator implemented one of these standards in their contract, they will receive royalties on ampule.

Royalties in swaps can be a bit complicated, so we came up with a new solution for calculating them. Royalties are only collected when a liquidity or "fungible" token (like ETH/WETH or MATIC) is included in a swap because when trading NFT-NFT there is no way to take a royalty percentage out. When you do include fungiible tokens, we will charge royalties based on the NFTs selected on the other side of the swap. We determine the "sale price" by dividing the total fungible token amount by the number of NFTs on the opposite side, and then take each NFT's royalty out of that amount.

For example, if you wanted to swap your friend 3WETH and a Gen K NFT in exchange for 3 NFTs from them -- let's say you want one of their Reddit Avatar with a 5% royalty, a y00t with a 3.33% royalty, and a Pluto Misfit with a 5% royalty -- Gen K would not recieve a royalty because there is no liquidity on the opposite side, but the "sale price" of the Reddit Avatar, y00t, and Pluto Misfit would be 1WETH each (3WETH divided by 3 NFTs) and their royalty amounts would be 0.05WETH (5% of 1), 0.0333WETH (3.33% of 1) and 0.05WETH, respectively.

Royalties are automatically included in all swaps and are always enforced.
Yes, open trades by default expire after 7 days. The creator of a trade can also cancel a trade at any time, though may need to pay gas to do so. If you receive a trade from someone else, you can decline it at no cost since you never deployed anything on-chain.
Currently, we can only support listing wallet assets for wallets with up to 1,000 assets per chain. If your wallet has more than 1,000 assets on a blockchain, please transfer the assets you wish to trade to a different wallet before creating the trade.

We are working to build a system that can handle larger wallets, and will roll this feature out as soon as possible. As a relatively small and agile team, we didn't have the resources to include this in our first launch but we have big plans for the future! Including hiring more builders :)
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