Legal

Judgment Interest Calculator

Legal basis: 28 U.S.C. § 1961 (post-judgment interest on federal civil judgments); state post-judgment interest statutes vary · checked 2026-10-04 · Rates and limits change — verify the current figures.

Winning a lawsuit usually does not mean the money arrives the same day. In most jurisdictions a judgment accrues interest from the date it is entered until it is paid, so the amount you can collect grows over time. In the federal courts, 28 U.S.C. § 1961 sets post-judgment interest at a rate equal to the weekly average one-year constant-maturity Treasury yield for the calendar week preceding the date of judgment, compounded daily. State systems differ widely: some set a fixed statutory rate, some tie the rate to a Treasury series or the prime rate, and a few let the contract rate carry through.

Because the federal rate floats week to week and every state chooses its own rule, the rate in this calculator is a user input rather than a preset. Enter the annual rate that applies to your judgment, the judgment amount, the judgment date and the payoff date, and the tool estimates the accrued interest and the total payoff amount. The interest itself follows the standard formula: principal times annual rate times elapsed time. For the compounded option, interest is added to the balance at the compounding frequency you choose, so the total grows slightly faster than simple interest.

Two practical cautions. First, elapsed time here is measured in whole days divided by 365.25; some statutes prescribe exact day counts or a 360-day year, which changes the result by a fraction of a percent. Second, in some states the rate can change mid-life of the judgment, for example when the statute ties it to a floating index that resets annually. This tool applies a single constant rate over the whole period, which is accurate for fixed statutory rates and a close approximation otherwise.

This is an educational estimate for planning, not legal advice, and post-judgment interest rules vary by jurisdiction and change over time. If you are a judgment creditor deciding whether to accept a payoff figure, or a judgment debtor checking a demand, verify the applicable rate and day-count method against the statute or court order in your jurisdiction, and consult a licensed attorney before accepting or paying a number.

Calculate

Accrued post-judgment interestsimple interest over 993 days$6,797

Total payoff amountprincipal plus accrued interest$56,797

Judgment principal$50,000

Annual rate applieduser input — verify the rate your statute or court order sets5.00%

Time elapsed993 days from judgment to payoff date2.72 years

Simple-interest comparisonmany state statutes use simple interest only$6,797

Interest accruing per dayat the rate entered on the current principal$7

How the math works

Simple interest = judgment principal × annual rate × elapsed years, where elapsed years = days between the judgment date and payoff date ÷ 365.25.
Compounded interest = principal × ((1 + rate ÷ compounding periods per year) ^ (periods per year × elapsed years)) − principal.
Total payoff = principal + accrued interest.
The annual rate is a user input: the federal rate floats weekly with the one-year Treasury yield, and state statutory rates differ.

Frequently asked questions

What rate applies to a federal judgment?

Under 28 U.S.C. § 1961, interest on a federal civil judgment accrues from entry at a rate equal to the weekly average one-year constant-maturity Treasury yield for the calendar week preceding entry, compounded daily. The rate is fixed for that judgment once entered.

Do states use the same rate as federal courts?

No. State post-judgment rates vary widely: some statutes set a fixed percentage, some float with a Treasury series or the prime rate, and a few carry the contract rate through. Enter the rate your state's statute or the court order specifies.

Is post-judgment interest simple or compounded?

Federal judgments compound daily. Many states award simple interest, while others compound annually or at another interval. The selector lets you compare both, but the controlling method is whatever the applicable statute provides.

From what date does interest start?

Usually the date the judgment is entered, though some jurisdictions allow prejudgment interest from an earlier accrual date, and some calculate from the date of verdict. Use the entry date unless your statute or order says otherwise.

How is elapsed time counted?

This tool uses actual days divided by 365.25. Some statutes use a 360-day year or count only certain days, which shifts the result slightly. For a demand letter or an acceptance of payoff, confirm the day-count method that applies.

Can the rate change while the judgment is unpaid?

It depends. Federal § 1961 rates are locked at entry, but some state statutes tie the rate to an index that resets annually, in which case the rate changes over the life of the judgment. This tool applies one constant rate.

Is this calculation binding on the debtor?

No. It is an educational estimate for planning. The enforceable amount is determined by the statute, the judgment and often the court clerk's calculation. Rules vary by jurisdiction, so consult a licensed attorney before demanding or paying a payoff figure.

This calculator is an educational estimate for planning purposes only. It is not legal advice, and post-judgment interest rates, compounding rules and day-count methods vary by jurisdiction and change over time. The applicable law depends on your state or federal court and the terms of the judgment. Consult a licensed attorney before relying on any interest figure.