Bonding curves and launches, explained

The short answer

A bonding curve is a deterministic pricing function that quotes a buy and sell price directly from on-chain reserves—no orderbook, no market makers. On Pump.fun, the curve is a constant-product formula, the same math family behind AMMs like Uniswap: two virtual reserves are multiplied together to form a fixed invariant, and every trade shifts one reserve up and the other down to keep that invariant constant (Pump.fun docs).

Every buy pushes the price up the curve. Every sell pushes it back down. Price impact scales with trade size, so a large buy or sell moves price more than a small one—there's no depth beyond what the curve's math provides.

How a curve launch actually works

On Pump.fun, the flow is standardized rather than negotiated per token:

1. Creation. Anyone deploys a token in roughly a minute for a small SOL fee, no code required. There is no presale and no team allocation handed out for free—the creator has to buy in on the curve like anyone else (Pump.fun docs).
2. Curve trading. The token is instantly tradable. Price discovery happens entirely on the curve—there's nothing to "add liquidity" to yet, because the curve's virtual reserves are the liquidity.
3. Graduation. Once the curve collects enough SOL to hit a set market-cap threshold, it closes automatically and irreversibly, and the entire accumulated pool migrates atomically to PumpSwap, Pump.fun's own DEX (Pump.fun docs). There's no human step, no delay, and no separate migration fee paid by the trader—the cost is taken from the coin's own liquidity.
4. Post-graduation trading. From that point, the token trades on PumpSwap's pool instead of the curve. Only a small share of tokens ever reach this stage—most curve launches never graduate.

What a curve trade costs

Bonding-curve trades on Pump.fun carry a combined fee, split between the token's creator, the protocol, and the pool itself. The exact split has changed over time as Pump.fun has adjusted its creator-reward program, so always check the current schedule in-app rather than assuming a fixed number carries forward indefinitely. This is one layer of a larger stack—see the full fee breakdown for how it combines with network fees, priority tips, and terminal fees.

Why this isn't the same as a normal DEX pool

A standard AMM pool has real reserves supplied by liquidity providers who can withdraw them—which is exactly the mechanism behind a liquidity-pull rug. A bonding curve's reserves are protocol-owned and locked into the curve's own logic until graduation, so there's no separate LP owner who can drain it early. That removes one specific risk, but it does not remove concentration risk, dev-wallet risk, or the basic fact that most tokens on the curve never graduate and simply die there.

Once a token does graduate, it behaves like any other AMM-based token—covered in reading a contract, including checks that still apply post-graduation: LP lock status, holder concentration, and mint/freeze authority.

For the exact graduation mechanics, canonical pool ownership, and the current PumpSwap fee schedule, see Pump.fun and PumpSwap: a deep dive.

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