But, that tool for mnemonic seed, I can't find where to input the private key.
No where to input it, I think he meant the use of Iancoleman to generate a HD paper wallet, or the use of Incoleman to generate the private key of an address for paper wallet purpose. 
Topic: Tutorial How to import old paper wallet to electrum (Read 162 times)
why?. is that risk also after I move that wallet file from the electrum folder to Flashdisk?
There is no guarantee that the device which has been online before hasn't been already infected. Also, when you delete a file from your computer, it's not completely removed from your hard drive. That's why there are some tools that can recover deleted files.
So, if you want to be completely secure, you should use an air-gapped devie. This means that you should use a device which has been always offline and will be never online.
Paper wallet addresses are legacy address, starting from 1. Using P2PKH while importing the wallet as seen on the image you included in your post, but it is worth knowing that if it is not nested segwit and native segwit addresses, if it is just legacy address, the P2PKH prefix is not needed, you can just past only the private key to generate the legacy address for you, I do not know of the future, but it still work that way till now.
Thanks, it's work when I tried.Some other ways to recover Bitcoin from old wallets with old formats. Electrum wallet is one of methods. Another one is using iancoleman's Mnemonic Code Converter.
But, that tool for mnemonic seed, I can't find where to input the private key.And it's also working for every private key, no matter where it's from, easy to import.
Yes, it works for WIF format, but it didn't work for Hex and Base64 Format, when we have the private key of Hex and Base64 Format, we have to convert it first to WIF format before import to electrum.Being offline at the time of importing the private key isn't enough.
why?. is that risk also after I move that wallet file from the electrum folder to Flashdisk?Have you even tried this? Your image shows an online wallet. An offline (cold) Electrum wallet won't show a balance.
Yes, I tried offline on my used address now.That picture I take while writing this tutorial on the forum.
today they have pots of money
Allow me:I was considering Electrum, only downside is that when creating a wallet, seed creation is exposed
Online:Install Electrum on your PC.
Import your address to create a watch-only wallet.
Preview the transaction, Copy the unsigned transaction. Put it on a USB stick.
Offline and running without hard drive storage:
Get a Linux LIVE DVD. Use Knoppix or Tails for instance, or any other distribution that comes with Electrum pre-installed.
Unplug your internet cable. Close the curtains. Reboot your computer and start up from that DVD. Don't enter any wireless connection password. Keep it offline.
Start Electrum. Import your private key.
Copy your unsigned transaction from the USB stick, load it into Electrum.
CHECK the transaction in Electrum. Check the fees, check the amount, check all destination addresses (character by character).
If all is okay, sign the transaction. Copy it back to your USB stick.
Turn off the computer. That wipes the Live LINUX from memory and all traces are gone.
Online:
Use your normal online Electrum to (check again and) broadcast the transaction.
Bonus:
After moving all your Bitcoin, and once the transaction confirmed, check if you own Forkcoins.
And important thing to do all step (step 1 - 4) above is do it OFFLINE or use the PC without connecting to internet.
I also don't like the idea of typing your recovery seed into a website because you want to get the right private key for a particular address or others, since this website works online I don't recommend using the same wallet for storing funds anymore, typing your keys online is already a red flag for me.
You do not have to trust using online site for seed phrase generation or to know which key belongs to an address using iancoleman, you can just make use of its html file offline, on an airgapped device.https://github.com/iancoleman/bip39/releases/tag/0.5.4
Some other ways to recover Bitcoin from old wallets with old formats. Electrum wallet is one of methods. Another one is using iancoleman's Mnemonic Code Converter.
The topic can help [overview] Recover Bitcoin from any old storage format
When you recover your wallets, do it offline.
Iancoleman is not recommendable for new crypto users because they can easily do something wrong, I also don't like the idea of typing your recovery seed into a website because you want to get the right private key for a particular address or others, since this website works online I don't recommend using the same wallet for storing funds anymore, typing your keys online is already a red flag for me.The topic can help [overview] Recover Bitcoin from any old storage format
When you recover your wallets, do it offline.
If I have to recommend this iancoleman website to anyone it will be crypto experts or those who want to get the fund in the wallet out and never use the wallet address ever again.
If you want to be completely secure, you should import your private key into an air-gapped device. Being offline at the time of importing the private key isn't enough.
And it may worth mentioning that, you will need two devices for making transaction from your paper wallet. One should be offline and the other one should be online.
I just want to add this as optional you can make an offline transaction using https://coinb.in/#newTransaction and generate a raw transaction where you need to copy and transfer it to the offline device where the Electrum is installed and then sign the transaction and transfer it back to the online device and go to https://coinb.in/#broadcast to broadcast the transaction.And it may worth mentioning that, you will need two devices for making transaction from your paper wallet. One should be offline and the other one should be online.
Just as hosseinimr93 commented before, yet an offline and online devices are needed. Offline for signing transaction while online for making PBST (which is the unsigned) transaction which is signed on offline wallet, and broadcasted online using the online watch-only wallet. This would be a good suggestion for OP as an alternative.
If you want to be completely secure, you should import your private key into an air-gapped device. Being offline at the time of importing the private key isn't enough.
And it may worth mentioning that, you will need two devices for making transaction from your paper wallet. One should be offline and the other one should be online.
And it may worth mentioning that, you will need two devices for making transaction from your paper wallet. One should be offline and the other one should be online.
I just want to add this as optional you can make an offline transaction using https://coinb.in/#newTransaction and generate a raw transaction where you need to copy and transfer it to the offline device where the Electrum is installed and then sign the transaction and transfer it back to the online device and go to https://coinb.in/#broadcast to broadcast the transaction.
Tested this on a legacy wallet I don't know if the segwit wallets will work.
Take note that your transaction can be replaced by a new one paying higher fee only if it has been flagged as RBF. Therefore, in the case you have made your transaction using a wallet that doesn't flag the transactions as RBF, you can't bump the fee even if you import your private key/seed phrase into a wallet supporting RBF.
This is kind of off-topic to this discussion but I just want to make something clearer about this which I know you know. This may depend on the wallet, on Electrum, replace-by-fee is set as default on the desktop version, while also it is default on the mobile version except you mark the transaction as final. Which means replace-by-fee is set by default on Electrum, but this might be different on another wallet just like you meant. When your transaction is stucked by low transaction fee rate you use initially, you can import it to another wallet to bump the fee or to make a CPFP transaction. If you don't know how to do it, you only can wait for network to clear its mempool or wait for mempool to drop your transaction.
Take note that your transaction can be replaced by a new one paying higher fee only if it has been flagged as RBF. Therefore, in the case you have made your transaction using a wallet that doesn't flag the transactions as RBF, you can't bump the fee even if you import your private key/seed phrase into a wallet supporting RBF. When your transaction is stucked by low transaction fee rate you use initially, you can import it to another wallet to bump the fee or to make a CPFP transaction. If you don't know how to do it, you only can wait for network to clear its mempool or wait for mempool to drop your transaction.
You are correct, but this thread is about how to import the private key of a paper wallet on Electrum which should be for spending. It imported already on Electrum, Electrum support replace-by-fee and child-pay-for-parent already, also that this topic is not about replace-by-fee or child-pay-for-parent. 
Knowing how to import a wallet from seed or private key is important and so helpful if an initial wallet does not allow you to bump fee (Replace-by-Fee) or use Child-pay-for-Parents (CPFP)
[Guide] Use CPFP if your stucked transactions from blockchain.com wallet.
When your transaction is stucked by low transaction fee rate you use initially, you can import it to another wallet to bump the fee or to make a CPFP transaction. If you don't know how to do it, you only can wait for network to clear its mempool or wait for mempool to drop your transaction.
[Guide] Use CPFP if your stucked transactions from blockchain.com wallet.
When your transaction is stucked by low transaction fee rate you use initially, you can import it to another wallet to bump the fee or to make a CPFP transaction. If you don't know how to do it, you only can wait for network to clear its mempool or wait for mempool to drop your transaction.
And important thing to do all step (step 1 - 4) above is do it OFFLINE or use the PC without connecting to internet.
If you want to be completely secure, you should import your private key into an air-gapped device. Being offline at the time of importing the private key isn't enough. And it may worth mentioning that, you will need two devices for making transaction from your paper wallet. One should be offline and the other one should be online.
You should create a watch-only wallet and create an unsigned transaction on the online device and sign the transaction on the offline device. After that, you should broadcast the transaction using the online device.
someone out there maybe forgets if they have an old paper wallet and keep it somewhere in a safe box. like the example picture below:
Yes, it's always important to be able to import a paper wallet, it's a basic step. And it's also working for every private key, no matter where it's from, easy to import.
Knowing the difference between importing and sweeping is also important, see Importing Vs Sweeping Private Keys; What you need to know.
Importing means, you'll get access to your original wallet (which you are importing) = you'll make your original wallet accessible in Electrum.
Sweeping means, you'll create a transaction sending your coins from your (paper) wallet to your preferred Electrum wallet = coins are transferred.
Some other ways to recover Bitcoin from old wallets with old formats. Electrum wallet is one of methods. Another one is using iancoleman's Mnemonic Code Converter.
The topic can help [overview] Recover Bitcoin from any old storage format
When you recover your wallets, do it offline.
The topic can help [overview] Recover Bitcoin from any old storage format
When you recover your wallets, do it offline.
Paper wallet addresses are legacy address, starting from 1. Using P2PKH while importing the wallet as seen on the image you included in your post, but it is worth knowing that if it is not nested segwit and native segwit addresses, if it is just legacy address, the P2PKH prefix is not needed, you can just past only the private key to generate the legacy address for you, I do not know of the future, but it still work that way till now.
Just simple, go to electrum.org and download it,
It is advisable to also provide the guide to users that downloaded the wallet to also verify its PGP signature. The links to a guide for the verification are on the official site or to use the one we recommend on this forum
someone out there maybe forgets if they have an old paper wallet and keep it somewhere in a safe box. like the example picture below:
Then, surprise today they have pots of money but forget how to use and import it because today he thing any change with make him doubt how to use it.
Just simple, go to electrum.org and download it,
1. after downloading go to wallet and select import private key like picture below:
2. in the next step, you have to be careful, because you don't indirectly insert the private key, you have to look the tab info how to import the private key following the address,
3. add p2pkh:L5m9u72Js3FiGt63dki5w3rf5ay4DLCvhGewFagHm16B6VV51ye4 on colomn like picture below;
4. And next, create password then, wallet already to use.
And important thing to do all step (step 1 - 4) above is do it OFFLINE or use the PC without connecting to internet.
Then, surprise today they have pots of money but forget how to use and import it because today he thing any change with make him doubt how to use it.
Just simple, go to electrum.org and download it,
1. after downloading go to wallet and select import private key like picture below:
2. in the next step, you have to be careful, because you don't indirectly insert the private key, you have to look the tab info how to import the private key following the address,
3. add p2pkh:L5m9u72Js3FiGt63dki5w3rf5ay4DLCvhGewFagHm16B6VV51ye4 on colomn like picture below;
4. And next, create password then, wallet already to use.
And important thing to do all step (step 1 - 4) above is do it OFFLINE or use the PC without connecting to internet.
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