Small Claims Interest Calculator
Calculate simple pre-judgment interest on a small claims or civil judgment using principal, annual rate, and number of days.
How to use this tool
- Enter principal amount, annual interest rate and days elapsed in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your interest accrued and the full breakdown beneath it.
This is an estimate, not legal advice. Laws vary by jurisdiction and individual circumstances. Consult a qualified attorney before making any legal decisions.
Estimate the pre-judgment interest owed on a small claims or civil dispute. This uses simple (non-compounding) interest. Statutory interest rates vary by state and claim type.
Formula
Interest ($) = principal × (annual rate ÷ 100) × (days ÷ 365)
Total owed ($) = principal + interest
How it works
This calculator applies the simple-interest formula using an actual/365 day-count convention, which is standard for most pre-judgment interest awards in civil courts. It does not compound interest; each day's interest accrues only on the original principal. The applicable annual rate is set by statute in most jurisdictions and should be verified against the relevant court rules before relying on this figure in legal proceedings.
Worked example
Worked example
- Inputs: principal = $1 000, annual rate = 10 %, days elapsed = 365.
- Interest: $1 000 × (10 ÷ 100) × (365 ÷ 365) = $1 000 × 0.10 × 1 = $100.
- Total owed: $1 000 + $100 = $1 100.
Interest accrued: $100; total owed: $1 100.
Key terms
- Pre-judgment interest
- Interest awarded by a court on a debt or damages from the date the claim arose until the date of judgment.
- Simple interest
- Interest calculated solely on the original principal, without compounding on accumulated interest.
- Actual/365 convention
- A day-count method that uses the exact number of elapsed days divided by 365 to calculate interest for any period.
- Statutory interest rate
- The annual interest rate prescribed by law for pre-judgment or post-judgment interest in civil matters within a jurisdiction.
- Small claims court
- An informal court designed to resolve low-value civil disputes quickly without the need for legal representation.
Frequently asked questions
- What is pre-judgment interest?
- Pre-judgment interest compensates the winning party for the time value of money between when the debt arose and when judgment is entered. Courts apply either the statutory rate or the contract rate.
- Is interest compounded in small claims?
- Most jurisdictions apply simple interest (not compound) for pre-judgment purposes. Post-judgment interest rules differ and may compound.
- What rate should I use?
- Use the rate specified in your contract, or look up your state's statutory post-judgment or pre-judgment interest rate. Common US rates range from 5% to 12% per year.