The credit bureaus have a their own proprietary methodology of calculating credit scores for individuals basis the credit history of the customer. There are several factors that they consider in the calculation of the score and give their own confidential weightages to each of the factors depending upon their potential to impact the credit profile of the customer. 

The key factors that impact the Credit Score are:

       1. On-time payments

The percentage of on-time payments for the past 36 months, any defaults or settlements sought

        2. Credit card utilisation

The percentage of your credit card limit you usually use

       3. Credit age

The amount of time for which you have an active credit history, i.e., applying for and getting loans or using credit cards

       4. Credit enquiries

The number of times you have applied for loans or credit cards in the last 12 months

      5. Credit mix

The different types of credit products you have used like personal loan, auto loan, home loan, credit card, etc.