How to use the prior conviction lookback calculator
Whether an old conviction still affects a new sentence depends on how long ago it was. Choose the length of the prior sentence, enter the date it was imposed or the release date if that is later, and add the date the new offense began. The tool shows when the prior stops counting and whether the new offense falls inside that window.
Korean criminal law uses a single three-year repeat offender period. The United States has no equivalent national rule. In federal cases USSG ยง4A1.2(e) counts a prior sentence exceeding thirteen months if it was imposed within fifteen years of the start of the new offense, or if the defendant was incarcerated during any part of that period, and counts other prior sentences imposed within ten years. Two qualifying priors can trigger the career offender enhancement in USSG ยง4B1.1. States run their own habitual offender and three-strikes statutes with washout periods that differ widely. This reflects the Guidelines as of September 2026.
The result is a screening estimate only. Whether a conviction qualifies also depends on the offense category, how related cases are grouped, juvenile adjudications and the effect of any expungement, and a sentencing court is not bound by an arithmetic date.
This calculator is for reference only and is not legal advice. Consult a licensed criminal defense attorney about your specific situation.
Frequently asked questions
Under USSG ยง4A1.2(e) a sentence longer than thirteen months counts if it was imposed within fifteen years of the new offense or if any part of the incarceration fell inside that window, so the later of the two dates usually controls.
No. State washout periods vary from a few years to no limit at all, and some states count only specific offense categories. Enter your state period in the override field to see the resulting date.