Sheep Lambing Calendar Generator
Enter your breeding season dates to generate the estimated start and end of your lambing period.
How this calculator works
By mapping the exact days the rams were with the ewes, we can project the earliest and latest standard lambing dates for the entire flock.
Formula used
Lambing Start = Breeding Start + Gestation. Lambing End = Breeding End + Gestation.
Example calculation
If rams were in from Oct 1 to Nov 1 (31 days), the lambing season will roughly be Feb 25 to Mar 28.
What to do with this result
Use the start date to schedule barn preparation, vaccinations, and shearing. Ensure you have adequate feed and labor during the calculated season.
Ready to track this for the whole flock?
One-off calculations are great for quick checks, but farm decisions are better when records are connected. HerdDeck Shepherd connects sheep records, weights, treatments, and feed costs in one easy app.
Try the DemoFrequently Asked Questions
It is very accurate for predicting the main drop, but individual ewes may vary by a few days.
Knowing the end date tells you exactly when you can stop checking for new lambs and close out the season.
If rams run year-round, you cannot use a calendar. You will have to rely on visual signs of pregnancy.
Many shepherds shear 4-6 weeks before the calculated lambing start date.