Calf Growth & ADG Calculator
is this calf on track to wean well?
Enter the calf's birth weight, today's weight and its age. See its average daily gain, the weight it should reach at weaning, and whether it is on track to double its birth weight.
Pre-weaning Growth
Average daily gain = (current weight − birth weight) ÷ age in days.
Status
Why Pre-weaning Growth Matters
Calves that grow well before weaning tend to calve earlier and milk better as cows.
A common goal is for a dairy calf to double its birth weight by weaning at about 8 weeks (56 days). The default target daily gain is for Holstein calves; for other breeds it is scaled to the breed's mature weight. You can change it to your vet's or nutritionist's target.
The status uses two checks: whether the calf is gaining at the target rate, and whether it will double its birth weight by weaning at that rate. Watch means close to target; Behind means well below it. Check milk intake, starter intake, water and health.
How to use this calculator
- Choose kg or lb, then the breed. For a breed that is not listed, choose "Other breed" and enter the weight of a typical mature cow in your herd.
- Enter the calf's birth weight, its weight today and its age in days.
- Check the target daily gain. The tool suggests one for the breed, shown under the box; type in your vet's or nutritionist's target if it is different.
- Read the status, the daily gain and the expected weaning weight. Weigh the calf again a few weeks later to see whether it is keeping up.
Reading the result
Average daily gain is the calf's total gain since birth divided by its age, so it is an average over its whole life. A calf that had a slow first week or two, or a bout of scours, can look behind even if it is growing well now. To see recent growth, take the gain between two weighings and divide it by the days between them. Expected weaning weight assumes the calf keeps gaining at the same rate until day 56, and compares that with double its birth weight. A calf can show Watch even when it beats the target gain, if it was heavy at birth and needs more gain to double that weight.
Common questions
How do I weigh a calf without a scale?
Use a calf weigh tape around the heart girth, or our animal weight calculator. Weigh at the same time of day, before feeding, for the fairest comparison.
What if my calf is behind?
Look first at how much milk or milk replacer it gets, whether it eats starter and drinks water, and whether it has had scours or pneumonia. Talk to your vet about any calf that keeps falling behind.
What weaning age does the tool use?
Day 56 (8 weeks). If you wean later, the calf has more time to double its birth weight, so judge it mainly by its daily gain against the target.
When is a calf ready to wean?
Weight is only part of it. The calf should be healthy and eating calf starter well every day before its milk is cut. Reduce milk over several days rather than stopping it all at once, and ask your nutritionist how much starter to wait for.
Can I use it for buffalo calves?
As a rough guide. Choose "Other breed", enter a typical adult buffalo weight from your herd, and set the target gain your vet recommends. Weaning ages for buffalo calves vary a lot between farms, so treat the day-56 projection with care.
Decision support only. Not a substitute for your veterinarian.