> For the complete documentation index, see [llms.txt](https://docs-v4.nftx.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs-v4.nftx.io/how-it-works/swaps-and-trade-ups.md).

# Swaps & Trade-Ups

Once a collection is a floor token, trading it is just a token swap — and NFTX layers a few NFT-native moves on top: instant floor swaps, trading up into rarer items, and permissionless re-pricing.

## Instant swaps

Every collection has a **Uniswap V4 pool** pairing its floor token with ETH, so you can trade **ETH ⇄ floor token** at any time, at the pool's price, with no counterparty to wait for.

Buying an NFT with ETH is the same swap with one extra step. Behind the scenes:

```
ETH → floor token → burn for an NFT
```

Most of your ETH buys one floor token in the pool, and that token is immediately burned to redeem a floor NFT from the vault. Selling is the reverse. You never have to hold the floor token yourself unless you want to.

### Floor-to-floor swaps

If you just want a *different* floor NFT — a different Milady, say — you can swap one floor NFT directly for another. Because both sides are worth exactly one floor token, it's an even trade: **no slippage, no ETH required.** Deposit yours, take another.

Swaps are one of the two places (alongside listings) where NFTX charges a fee. The pool's swap fee is collected through the [NFTX V4 Hook](/contracts/nftx-v4-hook.md); see [Fees](/core-concepts/fees.md) for how it works and where it goes.

## Trade-Ups: moving up into rarer items

Because listed items are priced in floor multiples, you can **combine floor value to trade up** into something rarer in a single transaction.

> You hold three floor Miladys but want a rare one listed at **3.00x**. Fill that listing with your three floor tokens — or with two floor tokens plus the ETH equivalent of the third — and you move straight from three floor items into one rare item. No selling, waiting, and re-buying.

The same fill pays the seller cleanly. When Evelyn lists a rare Remilio at 3x, she takes 1 floor token up front and the remaining 2 when it's filled — 3 tokens in total, which she can redeem for floor NFTs, sell, or keep. Trade-Ups turn "sell three, buy one" into one efficient move.

## Re-Listing: permissionless re-pricing

NFTX lets anyone **re-price a pooled item they don't own** — the mechanism that keeps listings honest. An arbitrageur can buy out an existing listing and immediately re-list the same item at a new price **without taking inventory risk**: they pay only the premium above floor to the current owner, plus the new listing fee.

> Carol deposits a Milady as a floor item. Bob notices it actually carries an underpriced rare trait, so he re-lists it at **1.25x** — paying just the new fee, since Carol's item was at floor — and captures the spread if it sells. If an item is already listed at 1.10x and Bob thinks it's worth 1.30x, he re-lists at 1.30x by paying the 0.10 premium to the current owner plus the new fee.

The current owner is always paid the premium they were owed as their listing is filled; the re-lister takes on the pricing bet. The result is a market that continuously pushes pooled items toward fair value.

{% hint style="info" %}
Re-Listing is a single-token action on the [Listings](/contracts/listings.md) contract (`relist`), and you can't re-list your own listing — only someone else's.
{% endhint %}

## Under the hood

Swaps route through the [NFTX V4 Hook](/contracts/nftx-v4-hook.md) and the collection's Uniswap V4 pool; the [Zap](/contracts/zap.md) contract bundles ETH wrapping and the swap so you can go straight from ETH to an NFT (or back) in one call. Trade-Ups and Re-Listing are part of the [Listings](/contracts/listings.md) contract.