user43545: I appreciate I can do offline singing with bitcoin-core, but it's complex.  To make it easier, I would have to download the entire blockchain.
I have searched up electrum, but can't seem to find a testnet option.  
Any ideas?

user10397: Testnet transactions have the same format as mainnet transactions, so you can just create a raw transaction on your online testnet wallet, and get it signed by Electrum with a private key it thinks is associated with a mainnet address (the version byte is different, so the same hexadecimal private key will generate a different address on the testnet and on the mainnet, but the signature will still be valid).

user10845: It looks like a testnet option was merged in early 2017, but I'm not sure if it was released:
https://github.com/spesmilo/electrum/commit/d042d6e970389f97331e9caae196bf7a3af1e293
https://github.com/spesmilo/electrum/issues/541

43545: <p>I appreciate I can do offline singing with bitcoin-core, but it's complex.  To make it easier, I would have to download the entire blockchain.</p>

<p>I have searched up electrum, but can't seem to find a testnet option.  </p>

<p>Any ideas?</p>
 10397: <p>Testnet transactions have the same format as mainnet transactions, so you can just create a raw transaction on your online testnet wallet, and get it signed by Electrum with a private key it thinks is associated with a mainnet address (the version byte is different, so the same hexadecimal private key will generate a different address on the testnet and on the mainnet, but the signature will still be valid).</p>
 10845: <p>It looks like a testnet option was merged in early 2017, but I'm not sure if it was released:</p>

<p><a href="https://github.com/spesmilo/electrum/commit/d042d6e970389f97331e9caae196bf7a3af1e293" rel="nofollow noreferrer">https://github.com/spesmilo/electrum/commit/d042d6e970389f97331e9caae196bf7a3af1e293</a></p>

<p><a href="https://github.com/spesmilo/electrum/issues/541" rel="nofollow noreferrer">https://github.com/spesmilo/electrum/issues/541</a></p>
