Post-Judgment Interest Calculator
Calculate how much post-judgment interest has accrued on a court award. Enter the judgment amount, applicable interest rate, compounding method, and number of days since the judgment was entered.
Post-judgment interest is the interest that accrues on a court judgment from the date it is entered until the date it is paid. This interest compensates the winning party for the time value of money while waiting for payment.
For federal court judgments, the interest rate is set by 28 U.S.C. Section 1961 and is based on the weekly average 1-year constant maturity Treasury yield. Federal post-judgment interest is calculated using simple interest, not compound interest. The rate is fixed at the time the judgment is entered.
State courts have their own rules. Some states set a fixed statutory rate (for example, New York uses 9% per year), while others tie the rate to Treasury yields or prime rate. Some states allow compound interest on judgments. Always check your jurisdiction's specific rules.
The formula for simple interest is: Interest = Principal x Rate x Time. For a $50,000 judgment at 5.5% for one year: $50,000 x 0.055 x 1 = $2,750. At 365 days, that works out to about $7.53 per day that goes unpaid.