How long is a donkey pregnant?
The Donkey Sanctuary puts donkey pregnancy at around 11 to 14½ months. That is a far wider range than a horse, so no single date is reliable. This calculator uses 12 months (365 days) as a planning midpoint, and shows you the earliest and latest dates across the 11 to 14½ month range.
Planning date = breeding date + 365 days
Earliest = about 11 months Latest = about 14½ months
Signs that foaling is near
The Donkey Sanctuary lists these signs. They are timed from the birth, not from the breeding date:
| When | What you may see |
|---|---|
| Up to 4 weeks before | The udder swells and subsides several times before its final enlargement |
| Last 72 hours | Milk often begins to run |
| Last 48 hours | Pelvic muscles loosen and the hindquarters lose tone |
| 24 to 48 hours before | Waxy colostrum may ooze from the teats |
| Close to foaling | She may become solitary, restless and off her feed, and may roll often |
With a window this wide, start watching for these signs from about 11 months, and keep your vet's number handy. Ask your vet about confirming the pregnancy and about care for the jenny.
Sample dates
| Bred | Planning date | Normal window |
|---|---|---|
| Thu, Jan 1, 2026 | Fri, Jan 1, 2027 | Wed, Dec 2, 2026 to Thu, Mar 18, 2027 |
| Sun, Mar 1, 2026 | Mon, Mar 1, 2027 | Sat, Jan 30, 2027 to Sun, May 16, 2027 |
| Fri, May 1, 2026 | Sat, May 1, 2027 | Thu, Apr 1, 2027 to Fri, Jul 16, 2027 |
| Wed, Jul 1, 2026 | Thu, Jul 1, 2027 | Tue, Jun 1, 2027 to Wed, Sep 15, 2027 |
| Tue, Sep 1, 2026 | Wed, Sep 1, 2027 | Mon, Aug 2, 2027 to Tue, Nov 16, 2027 |
| Sun, Nov 1, 2026 | Mon, Nov 1, 2027 | Sat, Oct 2, 2027 to Sun, Jan 16, 2028 |
For a horse, which has a narrower 320 to 370 day window, use the horse gestation calculator. Compare other animals in the animal gestation periods chart.
Frequently asked questions
How long is a donkey pregnant?
Around 11 to 14 1/2 months according to The Donkey Sanctuary. Twelve months is a common planning figure.
Why is the donkey gestation range so wide?
Individual jennies vary a lot, and the published range spans more than three months. That is why watching for physical signs matters more than counting days.
How do I know my jenny is about to foal?
The udder fills, milk often runs in the last 72 hours, waxy colostrum can appear 24 to 48 hours before, and the pelvic muscles loosen in the last 48 hours.
Is a donkey pregnant for longer than a horse?
Usually yes. A mare averages about 340 days and a jenny carries for around a year, with a wider range.
Sources
More gestation calculators
Cow Gestation Calculator
Calving date by breed, with the normal window.
Horse Gestation Calculator
Foaling date with the 320 to 370 day window.
Goat Gestation Calculator
Kidding date for dairy, meat and pygmy goats.
Sheep Gestation Calculator
Lambing date for ewes, with the normal window.
Dog Pregnancy Calculator
Whelping date with week-by-week milestones.
Cat Pregnancy Calculator
Kitten due date and stages of cat pregnancy.