RiskMemecoins are highly speculative, and most lose nearly all their value. Nothing here is financial advice. The risks in full
What is a bonding curve?
A bonding curve is a contract that sells a new coin at a price set by a formula: every buy raises the price and every sale lowers it. There's no order book and nobody making the market, so a coin can trade from its first second.
- pump.fun's curve is a constant-product formula, the same idea as Uniswap's pools.
- The curve holds the coin's tokens and the SOL paid for them.
- When the tokens for sale run out, the coin graduates to a regular exchange pool.
pump.fun describes its curve on its own page, The Pump.fun bonding curve. The numbers below come from the same formula memetools uses to build launches.
What is the formula?
The curve keeps two reserves, SOL and tokens, whose product stays the same after every trade. A buy that adds SOL must take out tokens to keep the product equal, and that's what sets the price.
pump.fun's starting numbers
The starting reserves are “virtual”: the 30 SOL isn't real money sitting in the curve. They're numbers that fix where the price starts and how steeply it climbs. Real SOL is only what buyers have paid in.
How does the price climb?
Slowly at first, then faster: the first 20 SOL into a pump.fun curve sells over half the tokens, while the last 25 SOL sells about a tenth. Price and market cap rise about fifteenfold from start to graduation.
| Real SOL in the curve | Tokens sold | Progress | Market cap |
|---|---|---|---|
| 0 | 0 | 0% | 28 SOL |
| 5 | 153 million | 19% | 38 SOL |
| 10 | 268 million | 34% | 50 SOL |
| 20 | 429 million | 54% | 78 SOL |
| 40 | 613 million | 77% | 152 SOL |
| 60 | 715 million | 90% | 252 SOL |
| About 85 | 793.1 million | 100% | About 411 SOL |
The same buy at different moments
Each 1 SOL buy pays pump.fun 0.0125 SOL first. Try other amounts in the pump.fun calculator, which uses the same formula.
What does bonding curve progress mean?
Progress is how much of the curve's 793.1 million tokens have been sold. At 100% the curve is sold out and the coin graduates.
- 50% progress means about 397 million tokens sold, which takes roughly 18 SOL of real buying.
- Progress isn't a share of the price or of the market cap. The last half of progress costs far more SOL than the first.
- Sales push progress back down, since tokens return to the curve.
What happens at 100% is in Memecoin graduation.
What happens when someone sells?
A sale runs the formula backwards: tokens go into the curve, SOL comes out, and the price drops. pump.fun takes its 1.25% from the SOL paid out.
- A large sale moves the price as much as a large buy, in the other direction.
- Because the curve always has a price, a coin on its curve can always be sold, though the price may be far below what was paid.
- Slippage is how far the price moves between asking for a trade and it happening: tools set a limit, and a trade outside it fails instead of filling.
Are other launchpads' curves the same?
The idea is the same and the numbers differ. pons, on Robinhood Chain, also sells a new coin on a bonding curve, priced in ETH, and graduates it at 4.2 ETH to a Uniswap pool.
- Each launchpad sets its own starting reserves, tokens for sale and graduation point.
- Fees differ too: about 1% plus the coin's creator tax on pons, 1.25% on pump.fun's curve.
- Some add rules for the first seconds, such as pons's anti-snipe tax.
See What is pons? and pump.fun vs pons.
Risks
A curve guarantees a price, not a good one. Memecoins are highly speculative, and most lose nearly all their value.
- Early buyers get far more tokens per SOL, and can sell to later buyers. The formula makes that structural, not a sign of anything.
- Most coins never fill their curve.
- Nothing here is financial advice.