Bond Calculator is designed to calculate analytical parameters used in assessment of bonds. The tool allows calculating net and dirty prices, accrued coupon interest (ACI), various types of bond yields, duration, as well as modified duration, convexities, PVBP, several types of spreads (G-spread, T-spread), giving the opportunity to analyze the volatility of the debt market instruments and evaluate the change of the bond price due to the yield change. Interface allows viewing key issue parameters. The Calculator also provides functionality on building simple models of coupon and discount bonds and international bonds to estimate price or yield quickly according to the imputed parameters.