A personal card and method of transaction validation for the protection of credit card use in malls, restaurants, telephone and Internet orders and use of ATM. The card generates a coded validation number based on a time code, a cardholder's PIN, and the amount of purchase in accordance with a unique code process for that particular personal card. The coded validation number is different for each transaction to prevent fraudulent use of the validation number. The cardholder provides the merchant the coded validation number in place of the usual static three or four digit verification number now in use. The merchant reports the transaction using normal reporting equipment and processes. The bank then validates the transaction by duplicating the time code and using the known PIN to determine the transaction amount. A method is disclosed to generate a time code by periodically rotating the columns and rows of a two dimensional matrix.