Calculator

Length (ft)

Width (ft)

Seeding Rate (lb per 1,000 ft²)

Bag Size (lb)

Seed Needed

Bags Needed

Seeding rate swings enormously by species and purpose — overseeding an existing lawn might call for 2–4 lb per 1,000 ft², while establishing a new lawn from bare soil can call for 6–9 lb. There's no single correct default, so check your seed bag's own label and enter its recommended rate here.

Enter the lawn's length and width to calculate seed needed and bag count.

How to Use the Grass Seed Calculator

Enter the lawn's length and width, set the seeding rate to whatever your seed bag recommends, and adjust bag size to match what you're buying.

seed needed (lb) = (length (ft) × width (ft) ÷ 1,000) × seeding rate (lb per 1,000 ft²)
bags needed = seed needed ÷ bag size (lb)

Seeding rate is the one number here that genuinely can't get a defensible universal default — it depends on the grass species, the seed's germination rate, and whether the job is overseeding a thin lawn or starting one from bare dirt. Overseeding typically calls for 2-4 lb per 1,000 ft²; a full renovation from scratch can call for double that or more, since bare soil has no existing turf competing for space.

The seed bag itself is the actual authority here, not this page — every reputable brand prints its own recommended rate for new lawns versus overseeding right on the label. Enter that number rather than guessing, and the calculator handles the arithmetic from there.