Dairy Gestation Calculator
Dairy gestation calculator preset to Holstein (279 days). Enter a breeding or AI date for a calving window, then plan dry-off about 60 days before due date around a 305-day lactation cycle.
Calculate calving dateChoose a breed and enter your breeding or AI date to see your calving window and milestones.
Dairy gestation calculator for Holstein, Jersey, and Brown Swiss
This dairy gestation calculator defaults to Holstein (279 days) so you can turn a breeding or AI date into a calving window built for dairy breeds — not the 283-day beef crossbred average. Switch the breed dropdown for Jersey (279) or Brown Swiss (291) when that matches your herd.
Dairy timing is tighter than beef because dry-off, fresh pens, and the 305-day lactation standard all hang on calving date. Use the due date above, then count back ~60 days for a target dry-off date on that cow.
Dairy breed gestation averages
| Breed | Average gestation | Notes |
|---|---|---|
| Holstein | 279 days | Most common US dairy default |
| Jersey | 279 days | Similar window to Holstein |
| Brown Swiss | 291 days | Longer — plan dry-off earlier relative to breed mates |
| Average beef / crossbred | 283 days | Use beef tools if that is your herd |
Individual cows still vary. Treat ±6–7 days as a normal window unless your vet advises otherwise.
Dry-off and 305-day lactation framing
A common dry period is about 60 days before calving. If the calculator shows a May 1 due date, plan dry-off around early March for that cow. Farms with shorter or longer dry periods should adjust — the 60-day figure is a planning default, not a prescription.
The 305-day lactation standard is how milk records are often compared. Calving date starts the next lactation clock. Missing the dry-off window by two weeks can cut udder recovery or leave cows milking with falling persistency — either way, the due date matters for parlor labor and transition-cow protocols.
How to calculate a dairy cow’s due date
Add breed gestation days to the breeding or AI date. A Holstein bred October 1 is expected to calve around July 7 (279 days). The calculator adds an early/late window so you can schedule preg checks, move-up dates, and dry-off lists.
For beef herds, use the cattle gestation calculator or Angus gestation calculator. For whole-herd season planning, use the breeding calendar.
Frequently asked questions
When should I dry off a dairy cow?
Many herds target ~60 days before expected calving. Confirm with your nutritionist or vet for your protocol.
Is Holstein gestation always 279 days?
279 is the breed average. Actual calving commonly runs several days either side depending on calf sex, parity, and sire.
Can I use this for Jersey cows?
Yes — select Jersey in the breed dropdown (279-day average) or keep Holstein if your herd average matches.