Bovine Gestation Calculator

For AI or a hand mating, the date of service. For a pasture mating, the first day of exposure.
Use your own herd or breed average. 0 uses the published species figure.
Plus or minus this many days around the due date. 0 uses the published normal range if there is one.
Expected due date
2026-10-11
Animal Gestation Calculator
Due date falls on
Sunday
What it is called
calving
Gestation length used
283
Days pregnant today
256
Days to go
27
Gestation complete
90.46 %
Stage of gestation
final third of gestation
Species
Cattle (beef cow)
Where the figure comes from
MSU Extension beef gestation tables are built on 283 days. Merck gives a Holstein-Friesian mean of 279 days, and gestation beyond 300 days is considered prolonged.
Worked out from Merck Veterinary Manual, The Reproductive System in Animals (gestation periods table) and 4 other sources.
No normal gestation range has been published for cattle (beef cow) in the cited sources, so only the mean is shown. Enter a due window to see a spread.
A planning estimate from published mean gestation lengths, not veterinary advice. Individual animals, breeds, litter size and sex of the offspring all shift the date; confirm pregnancy and timing with your veterinarian.

How this is worked out

4 steps
  1. Cattle (beef cow): published mean gestation of 283 days.
  2. 2026-01-01 + 283 days = 2026-10-11 (Sunday), the expected calving date.
  3. No published normal range is asserted for this species.
  4. On 2026-09-14 the animal is 256 days into gestation, 27 to go.

Results are general information, not financial, tax, legal, medical or engineering advice.