The bird feeder food calculator estimates how often you need to refill your feeder based on its capacity, the number of daily bird visits, and seed type. Stop guessing and keep your feeder consistently stocked.
Feeder Setup
Typical tube feeder: 16-32 oz. Platform feeder: 32-64 oz.
Count unique visits, not birds at once.
Seed Consumption Reference
| Seed Type | Top Attracted Birds | Per Visit (oz) |
|---|---|---|
| Black Oil Sunflower | Cardinals, chickadees, finches, nuthatches, jays | 0.15 |
| Nyjer / Thistle | Goldfinches, pine siskins, house finches, redpolls | 0.10 |
| Safflower | Cardinals, house finches, chickadees (squirrel deterrent) | 0.18 |
| Mixed Seed | Doves, sparrows, juncos, towhees | 0.20 |
| White Millet | Sparrows, juncos, doves, buntings | 0.12 |
How to Use the Bird Feeder Food Calculator
Knowing how often to refill your bird feeder prevents two problems: an empty feeder that drives birds away, and a full feeder that sits too long and develops mold. This calculator gives you a realistic refill schedule based on your feeder's capacity and the birds visiting it.
Step 1: Enter Your Feeder Capacity
Enter your feeder's seed capacity in ounces (or switch to kg). Most tube feeders hold 16-32 oz; platform feeders hold 32-64 oz or more. If you're not sure, weigh a full load of seed on a kitchen scale. Use the oz/kg toggle at the top to work in your preferred unit.
Step 2: Estimate Daily Bird Visits
Watch your feeder for 15 minutes on a typical morning and count individual landing events. Multiply by roughly 4-5 to estimate daily visits. A busy backyard feeder in good habitat might see 50-100 visits per day; a quieter location 5-20. Cardinal-heavy yards will consume more seed per visit than finch-heavy yards.
Step 3: Choose Seed Type and Bird Size
Different seeds have different consumption rates per bird. Nyjer is small and light — finches eat less weight per visit. Safflower and mixed seed are consumed faster. The bird size adjustment accounts for the difference in consumption between a sparrow and a blue jay.
FAQ
Is this bird feeder calculator free?
Yes, completely free with no signup required.
Is my data private?
Yes. All calculations run locally in your browser with no data sent to any server.
How much do birds eat per day?
A small songbird (sparrow/finch size) eats roughly 0.1-0.2 oz of seed per day. A larger bird like a cardinal eats 0.3-0.5 oz. A busy feeder with 10-20 visitors consumes 1-3 oz of seed daily, though this varies greatly by season and species mix.
What is the difference between sunflower, nyjer, and safflower seed?
Black oil sunflower attracts the widest variety of birds and is the most popular. Nyjer (thistle) is preferred by finches like goldfinches and siskins. Safflower is preferred by cardinals but avoided by most squirrels and starlings. Each has different typical consumption rates.
How full should I keep my bird feeder?
Keep feeders at least half full to attract birds consistently — birds will stop visiting an empty feeder and may not return quickly. In wet weather, clean out old seed frequently to prevent mold, which can be harmful to birds.
What is the best time to refill bird feeders?
Early morning is ideal since birds are most active feeding then. Check feeders before going to bed so they are full for the morning rush. In winter, fill feeders before forecasted storms — birds need extra calories in cold, wet weather.