Estimate pre-judgment or post-judgment interest on court awards using a user-entered governing rate.
When a court awards a money judgment, interest accrues on the unpaid amount. Post-judgment interest runs from the date of the judgment until paid, while pre-judgment interest may be awarded from the date the claim arose until the judgment date. Statutory rates vary by jurisdiction.
This calculator computes interest on a judgment based on the principal amount, the applicable statutory interest rate, and the number of days since the judgment (or since the cause of action accrued for pre-judgment interest). Use the current court order or statute for the applicable rate.
Judgment interest can add significantly to a court award over time. This calculator gives you a worksheet estimate of the interest owed so you can compare payment scenarios and check totals before using the number in a matter file.
Simple Interest = Principal × Annual Rate × Days / 365 Compound Interest = Principal × (1 + Rate/365)^Days − Principal Total Owed = Principal + Interest
Result: $8,136.99 interest — $108,136.99 total owed
Simple interest on $100,000 at 5.5% for 540 days = $100,000 × 0.055 × 540/365 = $8,136.99. Total owed = $108,136.99.
Federal courts apply 28 U.S.C. § 1961 using a Treasury-based rate. State courts use their own statutes, court rules, or contract-driven terms, and those can change over time. This worksheet therefore expects the user to enter the governing rate rather than relying on a baked-in jurisdiction table.
Accrued interest can materially change the total amount owed on a judgment. If the judgment is partially paid, if an appeal affects enforcement, or if the court order uses a different accrual method, the worksheet result should be adjusted to match the actual order.
Judgment interest can influence timing because delay may increase the total amount owed. This calculator helps compare those totals without claiming to replace the underlying court rule.
Last updated:
This worksheet multiplies the principal by the user-entered annual rate and elapsed days to estimate pre-judgment or post-judgment interest. It is intended to compare payment scenarios and check totals against the governing order or statute.
The page is intentionally conservative. It does not fetch live statutory rates, decide whether pre-judgment interest is available, or determine whether compounding applies in a specific jurisdiction. Those questions depend on the actual judgment, statute, and court rule.
The federal rate is based on the weekly average 1-year constant maturity Treasury yield, rounded to the nearest 0.01%. It changes regularly, so this page expects you to enter the current governing rate rather than relying on a built-in number.
Pre-judgment interest runs from the date the claim accrued (or demand was made) to the date of judgment. Post-judgment interest runs from the judgment date until the judgment is fully paid.
Most jurisdictions use simple interest for judgment interest. However, some states allow compound interest in certain circumstances, particularly for contractual claims where the contract specified compounding.
The governing rate is set by the applicable court rule or statute, not by the calculator. In settlement discussions, the parties can agree to different payment terms, which may change how much interest accrues.
Yes, post-judgment interest continues to accrue while a judgment is on appeal. The appellant may post a supersedeas bond to stay execution during the appeal.
Each payment is first applied to accrued interest, then to the principal balance. Future interest accrues only on the remaining principal.