Never put any significant amounts of coins in any online wallet. Keep multiple offline wallets with you and store the bulk of your coins in them. There are large number of options including USB sticks and paper-wallets.
Thanks, nice that I could set up multiple online accounts since that is easy for me.
Thanks. Does offline BTC wallet 100% safe?
Nothing is 100%. 99.999999%, perhaps; how many 9s depends on how strong your military grade physical security protections, how strong your vault doors, and how effective the armed guards and security support teams you have helping to protect the vaults holding the various segments of your wallet's private key.
It's as secure as the strength of your private key and how securely you generated that private key and kept it secret -- and the strength of the crypto algorithms.
A keypair generated using a flawwed random number generator, or based on a low-entropy passphrase ("Brainwallet") may be guessable and less than 99% safe.
You made your point clear. Thanks.
