Practical calving planning
Know when to watch the herd.
Turn breeding dates into realistic calving windows and a weekly herd plan—without replacing your spreadsheet.
Free cattle gestation calculator
For planning only. This tool does not confirm pregnancy, diagnose an animal, or predict an exact calving day.
Calving Window Planner
Plan the season, not just one date.
Paste rows from Excel or Google Sheets. We map common cattle-record headers, keep natural-service dates as ranges, and turn the result into a field-ready schedule.
Nothing pasted here is uploaded or saved in this first version. Export your result and keep control of your records.
CSV or tab-separated rows · dates may be YYYY-MM-DD or MM/DD/YYYY
4
Records ready
4
Weeks covered
0
Needs review
Season schedule
| Cow tag | Herd | Calculation source | Watch window | Midpoint |
|---|---|---|---|---|
| B12 | Heifers | Exposure 2026-06-01–2026-07-15 | Mar 1, 2027 — May 4, 2027 | Apr 2, 2027 |
| 104 | North pasture | Service 2026-11-12 | Aug 12, 2027 — Sep 1, 2027 | Aug 22, 2027 |
| 108 | North pasture | Service 2026-11-19 | Aug 19, 2027 — Sep 8, 2027 | Aug 29, 2027 |
| 215 | South pasture | Service 2026-12-03 | Sep 2, 2027 — Sep 22, 2027 | Sep 12, 2027 |
Built for trust in the field
Simple math. Visible assumptions.
The date engine is deterministic and uses date-only UTC logic, so daylight saving time and local browser settings cannot shift an animal by one day.
- 01
Bring your records
Enter one service date or paste a table. Common cow ID, herd, AI date, and exposure headers are mapped automatically.
- 02
Keep dates honest
A 283-day default stays editable. Natural-service exposure remains a range instead of being presented as one exact date.
- 03
Take the plan with you
Copy one result, add it to your calendar, or export and print the whole herd schedule without locking up your data.
Planning guidance should be checked against your herd history and veterinarian. Reference sources: