I created an ethereum paper wallet on an offline computer. Do I need to keep both the private key and the UTC/json file or can I just keep the UTC/json file and extract the private key from it. Thank you.
[Ethereum] Is it possible to extract private key from json/UTC file
private-key
Related Solutions
Yes, you can simply generate pairs of unencrypted or encrypted private and public keys. For example, use this bulk key generator:
1,"0xb7d3a6d96960c2e9650822be7c1cc4ebe8bb3718","9a130892d949ab5faf678ac6295d3ab05a434448b824c0dc43bf86a4c2bbf747"
2,"0xbf3407c1231b3612dc6d2da07f32208ed1e17ebd","e9a1bc1d7e5a815499009cf94139b3a4f532b0530df737247b6a0eccb65e5384"
3,"0x7637dc580f362786cbdc9e59a1baa9db4b46aa38","d7c8c4735ac5d665b7d9dd4a4d3dc61f4c1bffcad9b77d0f3aee5568d6dcdd10"
4,"0x395c3f208c09a9640880ae387331d7d58123bbd1","c0f075d2aa6510f75281b19f2c43771b99248f5784503344b21c590b8003419e"
5,"0x0d59b6bc0d014ee806230c4fee77e0c83bb6f453","0da749536ce1279d99663016428fe23a3799b842f982c6a1e81fa69cc0219a45"
6,"0xad17e413f8a47a07c8c7660f5c495b20176c59e0","994c6d8e93216ebd2f1e82662c00f3a7fb3e24f1245b4571791dc369f098bf20"
7,"0xa839ecc2305f433535eb1be00fc065ef728c61df","449fcc4846ec446e996653f3be7e81cf2f9c7df072ff2ece51e9f173928fb1cd"
Which outputs CSV: ID, public key (address), private key (here: unencrypted).
You can write them down. In general, I would recommend to encrypt them with a passphrase, but the output will be much more difficult to write down:
1,"0x5a594c44c194d9269025d07b9cf95e4b8fd767d2","U2FsdGVkX18TjcT/+fNBhHk1uPh1N72Vf3CLo/vkhor2+eKSEjeFbd13PbNcx78kwfwa0Gckv5yFjjQiR0qxyApPX6Buhs5e4IsYI90llPS0t75eJOz2b7qtPKlfX28T"
2,"0x052ce0c54dd7ec93fd513688fe954ae030889e6b","U2FsdGVkX1+XJEy6O2hw1N7PGnHtpQyrlLY+xD1J2X1TlgRqUB5gnQOS6rwi/mSEbdviLCjWKc3psQuV5UikS4wOmDunlWshGNTaoMIPj51Yh0KvfW22g6Evs1Z9COo3"
3,"0xbe8467807ea1374780d56a1bf9278fc1e1f5348a","U2FsdGVkX19SHpzNamqBl/JbmW2qzddPdQpIlKBadLstvlLtjmKI9YROxZlZEnHtK4mhPrKtTUWHGEF2sLAesVkBAqD71ORbWo6cEqa+C7pm4tkInuUTWWQVGEviNmGa"
4,"0xd903ff3313fdef8126b5f38c6775c0e34577ef33","U2FsdGVkX18V+us+TZ5ebawywwbW1eDtRjv8el6adTWcqf9Ag2nzWAtKlvZytCATEge4jzPZQaYJb7dZAMgjywGmxD63BPwZu7nc4hRzd+rWdVdT3NoyDE1WGJBa47Xp"
5,"0x425c6cd22c1673084d91bdc555115cf053a128a3","U2FsdGVkX1+BRDxxc4aDdYsdzjCDmHvBwiVp7GGFeBO2fc44pE+biTTaSz52Xrm9HhcwzHyQOxQc0KpRDckTiAV0VHb6MnfWcHKxlGTt5XzoMutZYrT6DWj8refcolp2"
6,"0x47bd738c482de1017c1bb44daed1174befe599f3","U2FsdGVkX1901zVkK+GEG1PNL5LWhAM/1EGGebUVKTBEqlEesgMliEb5bSGqQF+XbgmfefXjo/1lly8tPmEKz4vS4JNQU/m9gl9KMx/TADzz+mWbYj4WVo4KIqpaRdur"
7,"0x5600370a09691dea4e81735b86fb0b76182dcdee","U2FsdGVkX1+RwHwIB6SfPMAsoBGyWoz9QO72YY+J3hcfqWvlVnlW68jd5qAOaRVlZgnywpiKJmGjDCrTNR/ZiN0pHj3YlVN3+WdJ13qhFiMBxdLkrifblcNi+mXMCKm4"
A good alternative might a brain wallet, where you just have to remember the 20 words to generate the key pair. Here is one generator. Here is another (click "get address").
But as always, test this with small amounts first!
All you need to do is import the JSON file using mist. Open mist, press Ctrl I and drop your wallet json file into the resulting dialog.
Best Answer
The JSON file contains (in encrypted form) the private key, so that's all you need.