TheBusyFeederHummingbird nectar calculator
Measure the water first. For every four parts water, use one part refined white sugar. Make only the batch you can keep fresh.
Start with the water
Refined white sugar for 1 US cup of water
Four parts water to one part sugar, measured by volume. Let the nectar cool before filling your feeder.
The recipe is an ingredient measure
One US cup of water needs one-quarter US cup of refined white sugar. For 500 mL of water, measure 125 mL of sugar by volume. Do not assume the water and dry sugar volumes add to the exact final liquid yield.
Audubon advises using refined white sugar and tap water, bringing the solution to a boil, then cooling before filling the feeder. Do not add red dye, honey, brown sugar, molasses or artificial sweetener.
Keep the batch and the care routine together
A large reservoir is not a reason to leave nectar outside longer. Clean and replace it more often in warm weather, and act promptly if it becomes cloudy or moldy. Keep all food-contact ports and seals accessible.
The calculator does not predict consumption, the next refill, or hummingbird arrival dates. Local guidance is the right source for seasonal timing.