How can you speed up or cancel a transaction on Ethereum Blockchain?

Have you ever experienced pending transaction on ethereum blockchain? I have recently experienced it while sending 1up token from Metamask to Idex. It can make you confused, if you haven’t fallen in this situation before.

However, I successfully came out from this confusing situation. It was not so easy because first time I faced this problem and so I was completely puzzled. But Google helped me resolve the issue.

First solution that I found in Google search was not enough to help me resolve the problem. Following this solution, I made 3 more transactions to cancel the first one, but all of them fell in queue of the pending transactions.

Finally, I found the perfect way to cancel the first pending transaction, but remember there is no guarantee that it will work successfully. However, I have successfully canceled the first pending transaction using the same solution.

Now I would like to tell you the way I used to cancel the pending transaction. In order to complete this task, you need to download the latest version of MyEtherWallet from Github in your computer. Follow the following steps to download the file:

1) Open https://www.myetherwallet.com/ in your online computer.

2) Go to FAQ section and click on highlighted "See More".

3) A new page will open. Click on "Categories" Section.

4) Then click on "Offline".

5) Click on "Using Mew Offline (Cold Storage)" tab.

6) And then click on highlighted "here" word.

7) It will direct you to this github page : https://github.com/MyEtherWallet/MyEtherWallet/releases from where you will have to download latest version of zip file of myetherwallet to run it on your offline local computer. You must have to disconnect your internet while accessing MEW wallet offline using private keys or keystore file or mnemonic phrase.

Click on MyEtherWallet-vxxxx.zip.

8) If you have two computers in your home then keep one of them offline. Download MyEtherWallet-vxxxx.zip file into USB drive using online computer and then connect USB to your offline computer and extract MyEatherWallet zip file. In case of single computer, you will have to access offline MyEtherWallet without internet connection.

9) After extracting zip file, you need to open index.html to run MyEtherWallet in offline computer.

How to cancel a pending transaction on ethereum blockchain

In order to cancel the pending transaction, you need to make a transaction with 0 ETH to your own account by selecting higher gas price.

1) First you need to open myetherwallet.com in your computer which has internet connection.

2) Go to bottom of the page and click on "Send Offline Helper".

3) First you click on "Select Network" to check whether ETH network is selected. If not, then select ETH network.

4) Now enter the public address of your ethereum wallet under "Generate Information" section to know the Nonce of the pending transaction and Current Gas Price. Then click on "Export JSON File" to download the info and keep it in a folder.

The nonce is a numerical value which you find in every ethereum transaction. The nonce generated under "Generate Information" section is referred to the last transaction or current pending transaction from your ethereum wallet. You need this current nonce to cancel the pending transaction. To know more about Nonce, read the following article: https://kb.myetherwallet.com/en/transactions/what-is-nonce/

5) Now run myetherwallet in offline computer and login with your private keys. After logged in, you won't be able to see the balance, but you can generate a transaction.

6) Click on "Send" in the left sidebar.

7) Then click on "Send Offline" under Send menu.

8) Click on "import JSON" to upload JSON file that you download before from online myetherwallet. The file contains current gas price and the nonce of the pending transaction.

9) After importing JSON file, you need to check and edit the following field carefully:

Then click on "Generate Transaction" tab.

10) A pop-up window will open with signed transaction. Click on highlighted "Download JSON" word to download the JSON file and keep it in a folder.

11) Now log out from offline myetherwallet and connect your computer with internet. Visit online myetherwallet.com and go to send offline helper page. Click on "Signed Transaction" and upload JSON file that you download from offline wallet.

Then click on "Continue" tab. It will take you to "Transaction Details". Check every detail carefully and click on "Send". It will create a transaction hash which you will find under "Transaction Status".

12) Open the transaction hash in a browser. If everything is perfect, the transaction will be successful and the pending transaction will be dropped and replicated.

Remember, the nonce is very important. You must enter the same nonce that you find in the pending transaction detail. When miners find two transactions with the same nonce, they confirm the transaction which pays higher gas price and drops the transaction with lower gas price.

If you use Metamask to send a transaction, you can cancel it from there. It is very easy. But remember, you must choose higher gas price.

How to speed up a pending transaction on Ethereum Blockchain

Instead of cancel a transaction, you can speed up it on ethereum blockchain by selecting higher gas price. I have speed up a pending transaction from Metamask wallet. It is easier than the steps I have shown you to cancel a transaction.

Metamask wallet shows all transaction details that you have already made it. So, you can easily find pending transactions there.

Click on pending transaction. You will see two options "speed up" and "cancel". Just click on "speed up" tab, it will give you the option to choose gas price. Choose higher gas price and make the transaction. If everything is perfect, the transaction will be confirmed.