A user computing device generates a token while the user computing device is in an offline mode and not connected to an external network. The token includes information of an amount of cryptocurrency to be transferred from a user account to a receiving account and information of a first password for enabling the transfer. The token is signed by the user computing device with a private key while in the offline mode and the signed token is stored by the user computing device on a portable device. A receiving device receiving the signed token from the portable user storage device, authenticates a user corresponding to the user account based on the signed token, receives a second password, compares the first and second passwords for enabling the transfer, and transfers the amount of cryptocurrency from the user account to the receiving account based on the information included in the token.