Selling Tokens on PancakeSwap

[marcichan]

Hey, I tried your examples for buying tokens on PancakeSwap. Everything works fine. Now Im trying to sell tokens and I cant get it to work. Could you maybe make an example for that too, or give me some tips? Thanks!

[religion-counter]

I will upload a sell example Tomorrow.
Regards

[religion-counter]

I have uploaded the sell script: https://github.com/religion-counter/onlyone/blob/main/helper-scripts/sell-onlyone-pancakeswap.js
In order to sell you need to first approve the token for selling. This is the approve transaction executed by the script: https://bscscan.com/tx/0x5c87de77a431ced21532d1f10512d0cfd3ec4871f37effb83f62d6e6cd341772
And this is the actual sell again executed by the script: https://bscscan.com/tx/0x7faa7289646526a33e5ee5b46d4cb228d1aca87ec174c7c65679f9c43e2ecb3c
I also did many failed attempts like here: https://bscscan.com/tx/0x68df97ff5e9b17566d0dd5345558979609ddc55bfd71a0c494741ac870040307 and this address: https://bscscan.com/address/0xD41FeE0d3f057C01F831ECf31ddC9ef082ADe078 because I tried to sell without approving first :)

[marcichan]

Thank you alot! I was able to get it done late in the night, too :D

[religion-counter]

I am glad to hear that you were able to get it done.
Our mission is to educate more people about what is going on behind the crypto scene ;).

[marcichan]

Do you know what's the problem with this error?
https://bscscan.com/tx/0x7158bb87094da67e90c0afe934b36a7bed37c0085925d01790f46556b1bb91b7

[religion-counter]

You have to see whether the token you are trying to sell is approved for sell on the router. Also you can try to manually sell via the pancakeswap website and then copy the same transaction data.

[sircovsw]

I have an error when selling. Amount as in your example.
(node:19916) UnhandledPromiseRejectionWarning: Error: Transaction has been reverted by the EVM:

approve: https://bscscan.com/tx/0x39968ba83f35b2efaa654542e6695d7f9d50f6173b8dcb3b5e932c34ed6223b8
sell: https://bscscan.com/tx/0xfe25959a337bc31d4d0900cd055db2b6cda7a2cde4557c8225d224b4e0d0a3ab

Besides that, I have problems:

• how to determine the balance of a coin. In the wallet of coins: 150382.500540337410654784. The script outputs 150382500540337410654784. I don't understand how to format.
• how to correctly transfer the balance of the coin to the sale method

There are no problems with the purchase. Thanks for your script.

[religion-counter]

I have an error when selling. Amount as in your example.
(node:19916) UnhandledPromiseRejectionWarning: Error: Transaction has been reverted by the EVM:

approve: https://bscscan.com/tx/0x39968ba83f35b2efaa654542e6695d7f9d50f6173b8dcb3b5e932c34ed6223b8
sell: https://bscscan.com/tx/0xfe25959a337bc31d4d0900cd055db2b6cda7a2cde4557c8225d224b4e0d0a3ab

Besides that, I have problems:

* how to determine the balance of a coin. In the wallet of coins: 150382.500540337410654784. The script outputs 150382500540337410654784. I don't understand how to format.

* how to correctly transfer the balance of the coin to the sale method

There are no problems with the purchase. Thanks for your script.

Hi sircovsw,

The balance is the number of coins multiplied by the number of decimals. For your use case 150382.500540337410654784 has 18 decimals.
For your example (https://bscscan.com/tx/0xfe25959a337bc31d4d0900cd055db2b6cda7a2cde4557c8225d224b4e0d0a3ab) you have input 10000000000 UDOGE and want to receive 5400000000000 BNB for that. You can try to set amountOutMin to 10 or something small (which is something like sell on market price) and see whether the transaction will succeed then.

[religion-counter]

With the following script I was able to sell UDOGE for ONLYONE: https://bscscan.com/tx/0xa1695466014badc14265c577d5310cf2bd9c59a411d8930659d42cae6c9751c5
Please note that if you want to swap tokens for BNB you should call swapExactTokensForETHSupportingFeeOnTransferTokens
and if you want to swap tokens for other tokens you should call swapExactTokensForTokensSupportingFeeOnTransferTokens
Note that UDOGE gas 9 decimals so I multiply the original amount by 1e9: amountToSell*1e9

// Sells UDOGE for ONLYONE from pancakeswap for address ${targetAccounts[targetIndex].address}

var fs = require('fs')
var Tx = require('ethereumjs-tx').Transaction;
var Web3 = require('web3')
var Common = require('ethereumjs-common').default;

var web3 = new Web3(new Web3.providers.HttpProvider('https://bsc-dataseed.binance.org/'))
var BSC_FORK = Common.forCustomChain(
    'mainnet',
    {
        name: 'Binance Smart Chain Mainnet',
        networkId: 56,
        chainId: 56,
        url: 'https://bsc-dataseed.binance.org/'
    },
    'istanbul',
);


var targetAccounts = JSON.parse(fs.readFileSync('account-sell-udoge.json', 'utf-8'));

sellMulty();

async function sellMulty() {
    for (var i = 0; i < 1; ++i) {
        var targetAccount = targetAccounts[i];
        var amountToSell = 300012754.293006283; // Amount you want to sell
        var res = sell(targetAccount, amountToSell*1e9)
            .catch(e => {
                console.error("Error in sell:", e);
                process.exit(1);
            });
        console.log(res);
    }
}

async function sell(targetAccount, amount) {

    var amountToSell = web3.utils.toHex(amount);
    var privateKey = Buffer.from(targetAccount.privateKey.slice(2), 'hex')  ;

    var tokenAddress = '0xd2618bc9c9cdc40ff19e200a7d14a09799c0a152'; // UDOGE contract address
    var WBNBAddress = '0xbb4cdb9cbd36b01bd1cbaebf2de08d9173bc095c'; // WBNB token address
    var pancakeSwapRouterAddress = '0x10ed43c718714eb63d5aa57b78b54704e256024e';



    var routerAbi = JSON.parse(fs.readFileSync('pancake-router-abi.json', 'utf-8'));
    var contract = new web3.eth.Contract(routerAbi, pancakeSwapRouterAddress, {from: targetAccount.address});
    var data = contract.methods.swapExactTokensForTokensSupportingFeeOnTransferTokens(
        amountToSell,
        1,
        [tokenAddress,
         WBNBAddress,
         '0xb899db682e6d6164d885ff67c1e676141deaaa40'
        ],
        targetAccount.address,
        web3.utils.toHex(Math.round(Date.now()/1000)+60*20),
    );

    count = await web3.eth.getTransactionCount(targetAccount.address);
    var rawTransaction = {
        "from":targetAccount.address,
        "gasPrice":web3.utils.toHex(5000000000),
        "gasLimit":web3.utils.toHex(460000),
        "to":pancakeSwapRouterAddress,
        "value":web3.utils.toHex(0),
        "data":data.encodeABI(),
        "nonce":web3.utils.toHex(count)
    };

    var transaction = new Tx(rawTransaction, { 'common': BSC_FORK });
    transaction.sign(privateKey);

    var result = await web3.eth.sendSignedTransaction('0x' + transaction.serialize().toString('hex'));
    console.log(result)
    return result;
}

function sleep(ms) {
    return new Promise((resolve) => {
        setTimeout(resolve, ms);
    });
} 

[sircovsw]

var amountToSell = 300012754.293006283

Where did you get the value of the variable
var amountToSell = 300012754.293006283
?

Please tell me an example code to get 150382.500540337410654784 from 150382500540337410654784 or 93200875.137806421 from 93200875137806421

[sircovsw]

Please tell me an example code to get 150382.500540337410654784 from 150382500540337410654784 or 93200875.137806421 from 93200875137806421

Handled it

getTokenBalance = async (tokenAddress) => {
        let contractBuyToken = new this.web3.eth.Contract(this.tokenAbi, tokenAddress, {from: this.myContract})
        let balance = await contractBuyToken.methods.balanceOf(this.myContract).call()
        let tokenDecimals = await this.getTokenDecimals(tokenAddress)
        let unit = 'gwei'
        if (parseInt(tokenDecimals) === 18) {
            unit = 'ether'
        }
        balance = this.web3.utils.fromWei(balance, unit)
        return balance
    }

[sircovsw]

var res = sell(targetAccount, amountToSell*1e9)
...
var amountToSell = web3.utils.toHex(amount);

if tokenDecimals is 18, then it does not work:

Error: Error: [number-to-bn] while converting number 1.5038250054033741e+23 to BN.js instance, error: invalid number value. Value must be an integer, hex string, BN or BigNumber instance. Note, decimals are not supported. Given value: "1.5038250054033741e+23"

        let tokenDecimals = await this.getTokenDecimals(tokenAddress)
        let unit = 1e9
        let unit1 = 'gwei'
        if (parseInt(tokenDecimals) === 18) {
            unit = 1e18
            unit1 = 'ether'
        }

        amount = amount * unit;
        console.log(Math.floor(Date.now() / 1000), ' - ', 'amount', amount)

        let amountToSell = this.web3.utils.toHex(amount);
        console.log(Math.floor(Date.now() / 1000), ' - ', 'amountToSell', amountToSell)

[religion-counter]

var res = sell(targetAccount, amountToSell*1e9)
...
var amountToSell = web3.utils.toHex(amount);

if tokenDecimals is 18, then it does not work:

Error: Error: [number-to-bn] while converting number 1.5038250054033741e+23 to BN.js instance, error: invalid number value. Value must be an integer, hex string, BN or BigNumber instance. Note, decimals are not supported. Given value: "1.5038250054033741e+23"

        let tokenDecimals = await this.getTokenDecimals(tokenAddress)
        let unit = 1e9
        let unit1 = 'gwei'
        if (parseInt(tokenDecimals) === 18) {
            unit = 1e18
            unit1 = 'ether'
        }

        amount = amount * unit;
        console.log(Math.floor(Date.now() / 1000), ' - ', 'amount', amount)

        let amountToSell = this.web3.utils.toHex(amount);
        console.log(Math.floor(Date.now() / 1000), ' - ', 'amountToSell', amountToSell)

The token decimals are just for human readability. You can just multiply the number of tokens times 10 to the power of the token decimals. So for 1.5038250054033741e+23, e+23 means times 10 to the power of 23 so it equals 150382500540337410000000 and you can use this number.