Buying / selling a token

Buy and sell tokens on LaunchLab bonding curves

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Once a token is launched, users can buy and sell on the bonding curve until the fundraising goal is reached. This section covers how to integrate trading functionality.

How bonding curve trading works

LaunchLab uses bonding curves to determine token prices based on supply and demand:

• Buying increases the price — each purchase moves the price up along the curve

• Selling decreases the price — each sale moves the price down along the curve

• Price discovery — early buyers get lower prices, creating incentive for early participation

Trading continues until totalFundRaisingB worth of quote tokens have been collected, at which point the pool migrates to a Raydium AMM.

Buying tokens

Use buyToken() to purchase tokens with quote tokens (e.g., SOL).

  import { TxVersion } from '@raydium-io/raydium-sdk-v2'
  import { initSdk } from './config'
  import { PublicKey } from '@solana/web3.js'
  import BN from 'bn.js'

  const buyTokens = async () => {
    const raydium = await initSdk()

    const { execute, extInfo } = await raydium.launchpad.buyToken({
      mintA: new PublicKey('token-mint-address'),
      buyAmount: new BN(1_000_000_000),  // 1 SOL in lamports
      slippage: new BN(100),             // 1% slippage
      txVersion: TxVersion.V0,
    })

    console.log('Expected tokens:', extInfo.decimalOutAmount.toString())

    const { txId } = await execute({ sendAndConfirm: true })
    console.log('Transaction:', txId)
  }

Buy parameters

Parameter	Type	Required	Description
mintA	PublicKey	Yes	The token mint to buy.
mintAProgram	PublicKey	No	Token program (SPL or Token-2022). SDK detects if omitted.
buyAmount	BN	Yes	Amount of quote tokens to spend (e.g., lamports for SOL).
poolInfo	object	No	Pool state data. SDK fetches if omitted.
configInfo	object	No	Global config data. SDK fetches if omitted.
platformFeeRate	BN	No	Platform's fee rate. SDK fetches if omitted.
slippage	BN	No	Maximum slippage in bps (100 = 1%). Default: 100.
minMintAAmount	BN	No	Minimum tokens to receive. SDK calculates if omitted.

Buying exact token amount

Use buyTokenExactOut() to specify exactly how many tokens you want to receive.

const { execute, extInfo } = await raydium.launchpad.buyTokenExactOut({
  programId: LAUNCHPAD_PROGRAM,
  mintA,
  poolInfo,

  // Specify exact output
  outAmount: new BN('1000000000000'),  // Exact tokens to receive
  maxBuyAmount: new BN('2000000000'),  // Maximum quote tokens to spend

  slippage: new BN(100),
  txVersion: TxVersion.V0,
})

Selling tokens

Use sellToken() to sell tokens back for quote tokens.

const sellTokens = async () => {
  const raydium = await initSdk()

  const mintA = new PublicKey('token-mint-address')
  const sellAmount = new BN('500000000000')  // Tokens to sell

  const { execute, extInfo } = await raydium.launchpad.sellToken({
    programId: LAUNCHPAD_PROGRAM,

    // Token to sell
    mintA,

    // Sell parameters
    sellAmount,             // Amount of tokens to sell
    slippage: new BN(100),  // 1% slippage tolerance

    txVersion: TxVersion.V0,
  })

  console.log('Expected quote tokens:', extInfo.outAmount.toString())

  await execute({ sendAndConfirm: true })
}

Sell parameters

Parameter	Type	Required	Description
mintA	PublicKey	Yes	The token mint to sell.
sellAmount	BN	Yes	Amount of tokens to sell.
poolInfo	object	No	Pool state data. SDK fetches if omitted.
slippage	BN	No	Maximum slippage in bps (100 = 1%). Default: 100.
minAmountB	BN	No	Minimum quote tokens to receive. SDK calculates if omitted.

Selling for exact quote amount

Use sellTokenExactOut() to specify exactly how many quote tokens you want to receive.

const { execute } = await raydium.launchpad.sellTokenExactOut({
  programId: LAUNCHPAD_PROGRAM,
  mintA,
  poolInfo,

  // Specify exact output
  inAmount: new BN('1000000000'),        // Exact quote tokens to receive
  maxSellAmount: new BN('600000000000'), // Maximum tokens to sell

  slippage: new BN(100),
  txVersion: TxVersion.V0,
})

Advanced: Calculating quotes

Use the Curve utility to calculate expected outputs before executing trades (e.g. displaying expected amounts in the UI).

import { Curve, PlatformConfig } from '@raydium-io/raydium-sdk-v2'

// Fetch required data
const poolInfo = await raydium.launchpad.getRpcPoolInfo({ poolId })
const platformData = await raydium.connection.getAccountInfo(poolInfo.platformId)
const platformInfo = PlatformConfig.decode(platformData!.data)
const mintInfo = await raydium.token.getTokenInfo(mintA)
const slot = await raydium.connection.getSlot()

// Calculate buy quote
const buyQuote = Curve.buyExactIn({
  poolInfo,
  amountB: new BN('1000000000'),  // 1 SOL
  protocolFeeRate: poolInfo.configInfo.tradeFeeRate,
  platformFeeRate: platformInfo.feeRate,
  curveType: poolInfo.configInfo.curveType,
  shareFeeRate: new BN(0),
  creatorFeeRate: platformInfo.creatorFeeRate,
  transferFeeConfigA: mintInfo.extensions.feeConfig,  // For Token-2022
  slot,
})

console.log('Tokens out:', buyQuote.amountA.amount.toString())
console.log('Fees:', {
  protocol: buyQuote.splitFee.protocolFee.toString(),
  platform: buyQuote.splitFee.platformFee.toString(),
  creator: buyQuote.splitFee.creatorFee.toString(),
  share: buyQuote.splitFee.shareFee.toString(),
})

// Calculate sell quote
const sellQuote = Curve.sellExactIn({
  poolInfo,
  amountA: new BN('500000000000'),  // Tokens to sell
  protocolFeeRate: poolInfo.configInfo.tradeFeeRate,
  platformFeeRate: platformInfo.feeRate,
  curveType: poolInfo.configInfo.curveType,
  shareFeeRate: new BN(0),
  creatorFeeRate: platformInfo.creatorFeeRate,
  transferFeeConfigA: mintInfo.extensions.feeConfig,
  slot,
})

console.log('Quote tokens out:', sellQuote.amountB.toString())

Available quote methods

Method	Description
Curve.buyExactIn()	Calculate tokens received for a given quote token input
Curve.buyExactOut()	Calculate quote tokens needed for a specific token output
Curve.sellExactIn()	Calculate quote tokens received for a given token input
Curve.sellExactOut()	Calculate tokens needed to receive a specific quote token output

Referral fees

Integrators can earn referral fees by passing shareFeeRate and shareFeeReceiver parameters.

const { execute } = await raydium.launchpad.buyToken({
  // ... other params ...

  // Referral configuration
  shareFeeRate: new BN(5000),  // 0.5% referral fee
  shareFeeReceiver: new PublicKey('referrer-wallet'),
})

shareFeeRate cannot exceed maxShareFeeRate from the global config. Referral fees are paid in the quote token (e.g., SOL) and transferred directly to the shareFeeReceiver wallet.

Checking pool status

Before trading, verify the pool is still in trading status:

const poolInfo = await raydium.launchpad.getRpcPoolInfo({ poolId })

if (poolInfo.status === 0) {
  console.log('Pool is active - trading enabled')
} else if (poolInfo.status === 1) {
  console.log('Pool is migrating - trading disabled')
} else if (poolInfo.status === 2) {
  console.log('Pool has migrated - trade on Raydium AMM instead')
}

// Check progress toward migration
const progress = poolInfo.realB.mul(new BN(100)).div(poolInfo.totalFundRaisingB)
console.log(`Fundraising progress: ${progress.toString()}%`)