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Enter the number of visiting birds and the number of days. This birdseed feeder calculator allows 15 grams of seed per bird per day as a planning rule. For 6 birds over 7 days that is 630 grams, or 0.63 kg. For 4 birds over 7 days it is 420 grams, or 0.42 kg. Larger birds eat more than small garden birds, so treat the result as a starting amount and adjust it from what your feeder actually shows you.
This calculator uses 15 grams of seed per bird per day. That sits between the small bird guides of about 20 to 30 grams of mixed seed per day for sparrows and finches, and the lower intakes of the smallest birds, so it works as a simple feeder planning rule rather than a species exact figure.
Birds typically eat about a quarter to a half of their body weight in food each day, and the amount changes with species, size and season. Small birds such as sparrows and finches need roughly 20 to 30 grams per day, medium birds such as blackbirds and starlings need roughly 30 to 50 grams, and large birds such as pigeons and doves need roughly 50 to 100 grams. A cardinal may eat about 1.5 to 2 teaspoons of seed per day, while a goldfinch favours nyjer seed in much smaller amounts.
Birds eat more in winter than in summer, because cold weather raises their energy needs. Increase amounts in winter, offer high energy foods such as suet in cold spells, and reduce portions by roughly a third in summer when natural food is plentiful.
Sunflower seeds attract the widest variety of birds. Nyjer seed suits goldfinches, millet suits sparrows, and cracked corn suits ground feeding birds. Offer a variety where you can, and avoid cheap mixes heavy in red milo, which many birds discard.
Fill feeders with enough seed to last 1 to 3 days where bird traffic allows, rather than filling to the top for weeks. Wet or old seed can develop mould, which can harm birds, and excess seed attracts rodents and pests. Good feeder cleaning prevents spoilage, and a balanced garden bird diet includes fresh seed, clean water and varied seed types for each sparrow and other visitor.
Count the birds that visit at one time, not every bird you see across a whole day, or you will double count the same visitors. Watch for a few days, take the busiest count as your starting bird number, then adjust the calculator result up or down from refill speed.
For 6 birds over 7 days: seed 630 grams, or 0.63 kg. For 10 birds over 14 days: seed 2100 grams, or 2.10 kg. For 4 birds over 7 days: seed 420 grams, or 0.42 kg.
About 15 grams per bird per day as a planning rule. Small birds need roughly 20 to 30 grams, medium birds 30 to 50 grams, and large birds 50 to 100 grams.
For 6 birds, about 630 grams for a week. Multiply your bird count by days and by 15 grams for other combinations.
Yes. Birds eat more in winter to stay warm, so increase feeder amounts in cold weather and offer high energy foods such as suet.
Sunflower seeds attract the widest variety of garden birds. Add nyjer for goldfinches and millet for sparrows to widen the mix.
Aim for enough seed to last 1 to 3 days, depending on bird traffic and weather, rather than leaving seed sitting for weeks.
Yes. Wet or mouldy seed can develop harmful mould, so remove damp seed, clean feeders regularly, and store seed dry.
Yes. Provide fresh water alongside seed, especially in dry seasons and in freezing weather when natural water is hard to find.
Birds scatter seed while foraging, and they discard seeds they do not like. Reduce the amount, change the mix, or move the feeder if waste stays high.