Credit rating is a traditional measurement of credit risk in financial markets. This paper introduces an innovative approach based on implied ratings defined by CDS spreads. Using this approach the credit risk can be better managed because CDS are provided on daily basis. The implied rating is compared with credit ratings provided by Moody´s, S&P, and Fitch. The model of implied rating deals only with sovereign ratings. 52 countries were chosen for comparison of both types of above-mentioned ratings. The model uses cumulative default probabilities (CPD) derived from CDS spreads and the main results are CPD intervals which define implied credit ratings. For those countries where the credit rating and implied credit rating are different, the paper shows how implied rating can serve as a signal for potential upgrade or downgrade of the credit rating provided by rating agencies. The presented model is also used to verify ratings provided by Moody´s, S&P, and Fitch in cases where these agencies provide different ratings for a specific country. This is especially important when some ratings are investment-grade and others are speculative-grade.