Abstract: A method and system for anonymizing data to be transmitted to a destination computing device is disclosed. Anonymization strategy for data anonymization is provided. Data to be transmitted is received from a user computer. Selective anonymization of the data is performed, based on the anonymization strategy, using an anonymization module. The data includes a plurality of characters and defines a clear data. A modified clear data with number of characters greater than the clear data is formed using the clear data, a delimiter data and a pad data. The modified clear data is anonymized to derive an anonymized data. The anonymized data is transmitted to the destination computer over a network. In one embodiment, a portion of the pad data is selected as a seed value to generate an initialization vector to anonymize the clear data.