Pig Gestation Calculator

Enter a breeding date and this calculator gives you the sow’s expected farrowing date using the standard swine gestation length of 114 days — the old “3 months, 3 weeks, and 3 days” rule — plus the 21-day heat-cycle check dates so you know when to watch a sow that may not have settled.

How it works

• Due date: breeding date + 114 days.
• Heat checks: if the sow didn’t settle, she returns to heat about every 21 days after breeding — the calculator lists those recheck dates.
• Plan farrowing crates, vaccinations, and show-pig target dates backward from the due date.

Open the interactive calculator — free, no signup.

Breeding this cycle? Browse boars and reserve semen doses from boar studs across the country, or find a boar stud on BoarStud.com.