Weaning Weight & From Birth Weight & ADG
Weans calves
Enter birth weight, average daily gain and age at weaning to get the weaning weight, total gain and ADG — a key measure of pre-weaning growth and dam milking ability.
Project weaning weight
Next: aim to hold the calf at 0.7 kg/day with quality creep feed and milk; a heavier weaning weight at 205 days drives a better sale or growing-on start.
ADG depends on dam milk, creep feed, health and genetics; 205 days is the standard adjusted weaning age used for beef performance comparisons.
Weaning weight — key facts
- Weaning weight
- birth wt + ADG × age
- Total gain
- ADG × age at weaning
- Measures
- Growth + dam milk
- Calf pre-wean ADG
- ≈ 0.7–1.1 kg/day
- Standard age
- often 200 days (beef)
- Below target
- flags feed or health
- Works for
- calves, lambs, kids
- Privacy
- Runs in your browser; nothing uploaded
The number that grades both the calf and its mother
A calf, lamb or kid's weaning weight equals its birth weight plus average daily gain times age at weaning. It is one of the most telling figures in livestock farming because pre-weaning growth comes mostly from the dam's milk — so weaning weight grades the offspring's growth and the mother's milking ability in a single number. Comparing it to a target flags nutrition or health issues early, while there is still time to act.
This tool gives the weaning weight, total gain, weaning age and average daily gain from your birth weight, ADG and age inputs. Use it to project sale weights, rank cows and ewes by the calves they raise, and catch under-performers against a breed target. Pair it with the Average Daily Gain, Colostrum Feeding and Heifer Breeding Weight tools for a full growth plan.
Project weaning weight
Turn birth weight and ADG into a number.
Grade the dam
Spot poor milkers from light offspring.
Hit a target
Compare growth to a breed benchmark.
Catch problems early
Flag nutrition and health gaps in time.
Frequently Asked Questions
What is weaning weight?+
Weaning weight is how much a calf, lamb or kid weighs when it stops nursing and is taken off milk. It equals birth weight plus average daily gain multiplied by age at weaning. It is one of the most important early performance measures because it captures both the animal's own growth and how well its dam fed it.
How is weaning weight calculated?+
Weaning weight = birth weight + (average daily gain × age at weaning in days). For example a calf born at 35 kg gaining 0.9 kg/day for 200 days weans at 35 + 0.9 × 200 = 215 kg. The calculator also returns the total gain and the average daily gain so you can compare animals fairly.
Why does weaning weight matter?+
It is a key measure of pre-weaning growth and dam milking ability — a heavy calf usually means good genetics, plentiful milk and sound health. Weaning weight strongly influences later growth, sale value and the dam's worth as a breeder, so it is widely used to rank cows and select replacements.
What does weaning weight tell me about the dam?+
Pre-weaning growth comes mostly from the mother's milk, so a low weaning weight relative to the herd often points to poor milking ability, mastitis or thin condition in the dam. Tracking weaning weights across cows highlights which mothers raise the heaviest offspring and which to cull.
What is average daily gain (ADG)?+
ADG is the weight an animal puts on per day — total gain divided by the number of days. For pre-weaning calves it is typically 0.7–1.1 kg/day on good milk and pasture; lambs and kids gain far less in absolute terms but a high proportion of birth weight. The calculator shows ADG so you can benchmark growth.
Why compare weaning weight to a target?+
A target weaning weight for your breed and system is a benchmark. Animals well below target flag nutrition or health issues — poor milk, parasites, disease or feed shortage — early enough to act. Hitting or beating target confirms the dam, feed and management are working.
What is a 200-day or adjusted weaning weight?+
Because calves are weaned at different ages, weights are often adjusted to a standard age (commonly 200 days for beef cattle) so they can be compared fairly. Using birth weight and ADG, you can estimate weight at any chosen age — set the weaning age to your standard to get a comparable figure.
Does this work for lambs and kids too?+
Yes — the same birth weight + ADG × age formula applies to lambs and kids, just with smaller numbers and shorter pre-weaning periods. Enter the species-appropriate birth weight, daily gain and weaning age and the calculator handles it the same way as for calves.
Are the figures exact?+
They're solid planning figures. Real weaning weight depends on day-to-day variation in milk, pasture, weather and health, and ADG is rarely perfectly constant. Weigh animals directly when you can, use the estimate for planning and target-setting, and treat it as a guide, not a guarantee.