I think the safest Wallet is Blockchain.
Blockchain is the 1st bitcoin wallet in the world and the most widely used. And being the first wallet to provide a crypto bitcoin storage facility, Blockhain is closely related to the current bitcoin economic growth.
Hopefully my answer helps you.
If you mean blockchain.info then youre wrong. Its an online wallet so can be hacked. Nowhere near as safe as Bitcoin QT or hardware & paper wallets.
I do use blockchain.info for smaller spends & have never had a problem with it but no way would I ever leave my main stash on an online wallet.