Buying and selling
What a trade costs, how slippage works and what can stop a trade.
Read the Fee Clock
Every token page has a Fee Clock under its price chart. It shows what a buy and a sell cost at this moment, Bot Tax included, and when the next change in the schedule happens. If you're connected, the sell fee includes your own Hold Streak discount. The trade panel quotes any amount, even before you connect a wallet, shows where the fee goes, and tells you when waiting a little would make your trade cheaper.
What you pay with
Each token trades against one paired asset, chosen by its creator at launch: ETH, USDG or a stock token. You buy with that asset and receive it when you sell, and fees and holder rewards are paid in it too.
So that tokens with different pairs are easy to compare, a token page shows its price, chart and market cap in dollars, converted at the paired asset's current price. Explore, the site totals and your profile show dollar values too. They use live prices: ETH from CoinGecko, USDG at $1, and stocks from Robinhood's price feed. Dollar values are for comparing; what you actually pay and receive is the paired asset, and the trade panel shows amounts in it. Some paired assets carry their own risks: see Paired-asset risks.
Bonding curve and graduation
Every CAST token starts on a bonding curve. The Fee Hook runs it inside the token's own Uniswap v4 pool: it sells tokens to buyers and buys them back from sellers at a price set by a fixed formula, which rises as people buy and falls as they sell. While a token is on its curve, the curve itself is the market. There is no pool liquidity yet.
Each paired asset has a graduation target of about $10,000: 4.2 ETH or 10,000 USDG, for example. Once the curve has raised its target, the token graduates in the same transaction as the buy that gets it there. That buyer gets the curve's last tokens, then everything the curve raised and the rest of the tokens go into one Uniswap v4 position at exactly the curve's final price, so the price carries on smoothly. Whatever is left of that buy is made in the new pool, and from then on the token trades there. The position is locked forever.
With no creator allocation, 1 billion tokens open at about $3,300 and graduate at about $48,000. The curve sells about 79.3% of the tokens; the rest go into the pool. Each pair's exact figures are on Network and contracts.
A token page shows a progress bar for how much of its target the curve has raised. On Explore, the Almost graduated filter shows tokens that have raised at least half their target, and Graduated shows tokens that trade in their pool.
Buying
You spend the token's paired asset and receive tokens. The fee is taken from what you pay before it reaches the curve or the pool, so the tokens you get are priced on what's left. If the token has a burn share, that part of the fee is taken in tokens and burned instead.
| Part | When | Paid in |
|---|---|---|
| Bot Tax | Early buys, on its own schedule: at most 50%, and 0% within 24 hours of launch | The paired asset |
| Buy fee | Every buy, following its schedule | The paired asset, except the burn share |
| Pool fee | Every trade after graduation, 0.3% | Stays in the pool |
With ETH, a buy is one transaction. With an ERC-20 such as USDG or a test stock, the CAST Router needs your permission to take it. Your wallet asks you to sign a permit for exactly the amount you're spending: a free signature that the buy uses in the same transaction. For an asset without permit support, you approve the router in a separate transaction first.
Selling
Each sell takes two transactions. First your wallet asks you to approve the CAST Router to move exactly the amount you're selling, then you confirm the sell. The approval covers only that sell, so the next one asks again. You receive the token's paired asset, and the sell fee is taken from it. On tokens where the sell fee follows Hold Streak, holding longer lowers it.
Slippage and price impact
Your trade moves the price, and the bigger the trade compared with the curve or the pool, the more it moves. Other trades can also land just before yours. Slippage is how much worse than the quote you'll accept: the trade panel shows the least you could receive (0.5%, 1% or 3%), and the transaction reverts rather than give you less. Each quote is also valid for 10 minutes, so a trade left waiting in your wallet can't confirm later at an old price.
Max wallet
Some tokens cap how much one wallet can hold, often only early on. A buy or an incoming transfer that would take a wallet over the cap reverts. CAST simulates every trade before you sign, so you see a warning instead of a failed transaction. While the cap applies, buys only go through the CAST Router (see Trading in other apps).
Max wallet applies on the bonding curve too, so a token with a tight cap needs many different wallets to buy before it can graduate.
Trading in other apps
CAST pools are ordinary Uniswap v4 pools with a hook, so other apps and routers can trade them. The fees are charged either way. Two things differ:
- Only the CAST Router tells the Fee Hook who is trading, so a sell through any other router gets no Hold Streak discount and pays the full sell fee.
- While a token's max wallet applies, only the CAST Router can buy it. Other routers could leave bought tokens where the token can't check the cap, so the Fee Hook refuses their buys. Selling through them always works, and once the cap lifts any router can buy.
Until a token graduates, its curve only takes trades with a fixed amount in (exact input), which is what the CAST Router always sends. An app that asks for an exact amount out gets an error until then.
Max wallet and Hold Streak are enforced by the token itself, so they apply wherever the token goes.