Animal Gestation Calculator

Alpaca Gestation Calculator

Last updated

A alpaca's gestation period is about 345 days, or roughly 11 months and 1 week, though it ranges from 335 to 355 days depending on breed and individual animal.

Calculate a cria due date

What do you know?

Estimated birthing date

Friday, 8 October 2027

Earliest

28 Sept 2027

Latest

18 Oct 2027

345 days remaining0% complete

0 of 345 days elapsed

Milestone timeline

Key Alpaca pregnancy milestones with calculated calendar dates
DayMilestoneDate
14Spit-off test: an open female sits for the male, a pregnant one spits11 Nov 2026
45Ultrasound or progesterone test confirms the pregnancy12 Dec 2026
90Recheck — early embryo loss is common in alpacas26 Jan 2027
240Clostridial booster so the cria gets antibodies via colostrum25 Jun 2027
300Shear or crutch her and lift the ration for the final growth phase24 Aug 2027
335Earliest normal birthing — start morning checks28 Sept 2027
345Expected birthing (unpacking)8 Oct 2027

What to do next

How to use the alpaca gestation calculator

  1. 1. Choose what you know. Enter the breeding date to get a due date, or switch to the target due date mode to work backwards to the breeding date you need.
  2. 2. Refine the inputs. The calculator uses the 345-day average for this species.
  3. 3. Plan around the range. Use the earliest and latest dates and the milestone timeline to schedule checks, feed changes and preparation of the birthing area.

How long is a alpaca's gestation period?

The average is 345 days from breeding to birthing, about 11 months and 1 week. Anything between 335 and 355 days is normal, and a typical litter is 1 cria. Treat the calculated date as the middle of that window rather than a fixed appointment.

Alpaca gestation table: breeding date to birthing date

Breeding dates one week apart with the matching birthing date at 345 days.

Twelve sample Alpaca breeding dates and their calculated due dates
Breeding dateExpected birthing date
28 Oct 20268 Oct 2027
4 Nov 202615 Oct 2027
11 Nov 202622 Oct 2027
18 Nov 202629 Oct 2027
25 Nov 20265 Nov 2027
2 Dec 202612 Nov 2027
9 Dec 202619 Nov 2027
16 Dec 202626 Nov 2027
23 Dec 20263 Dec 2027
30 Dec 202610 Dec 2027
6 Jan 202717 Dec 2027
13 Jan 202724 Dec 2027

Working backwards from a target birthing date

If you want crias on the ground in a particular week, switch the calculator to target date mode and enter the date you are aiming for. It subtracts 345 days to give the breeding date to book, plus the earliest and latest service dates that still land inside your window.

Alpaca gestation calculator FAQs

How do I calculate a alpaca due date?

Enter the breeding or mating date and the calculator adds the average alpaca gestation of 345 days. It also shows the earliest (335 days) and latest (355 days) dates that are still normal.

Should I use the first or last mating date?

If mating happened over several days, run the calculator for the first and the last date. The cria is most likely to arrive between the earliest result of the first date and the latest result of the last date.

Can I work out when to breed for a target alpaca due date?

Yes. Switch to target due date mode and enter the date you want; the calculator subtracts 345 days to give the breeding date, plus the earliest and latest breeding dates that still fit.

How accurate is the alpaca due date calculator?

It gives a planning estimate from published averages. Most births fall inside the 335–355 day window shown, but ask a vet to confirm the pregnancy and check anything outside that range.

More gestation pages

Livestock gestation chart