Grass Seed Calculator

Using the right amount of seed is the difference between a thick lawn and a thin, patchy one. Choose your grass and whether it’s a new lawn or overseeding, the calculator fills in a typical rate and works out how much to buy.

View formula

Seed (lb) = seeding rate (lb per 1,000 sq ft) × area (sq ft) ÷ 1,000 Metric: seed (kg) = rate (g/m²) × area (m²) ÷ 1,000 1 lb / 1,000 sq ft ≈ 4.88 g / m²

How to use the Grass Seed Calculator

Enter the lawn area (or length × width).
Choose the grass type and whether you’re starting from bare soil or overseeding.
Check the seeding rate against your seed bag and adjust if needed.
Enter the bag size and press Calculate.

Typical seeding rates

Rates are pounds of seed per 1,000 sq ft (new lawn / overseeding). Use the label on your seed when it differs, coated seeds and blends often need more.

Grass	Typical rate (lb/1,000 sq ft)	Calculator default	Climate
Kentucky bluegrass	2 to 3 / 1 to 2	2.5 / 1.5	Cool-season
Tall fescue	6 to 10 / 3 to 5	8 / 4	Cool-season
Perennial ryegrass	7 to 9 / 4 to 5	8 / 4	Cool-season
Fine fescue	3 to 5 / 2 to 3	4.5 / 2.5	Cool-season
Bermudagrass (hulled)	1 to 2 / 0.5 to 1	1.5 / 1	Warm-season
Zoysiagrass	1 to 2 / 0.5 to 1	1.5 / 1	Warm-season
Centipedegrass	0.25 to 0.5	0.5 / 0.25	Warm-season
Bahiagrass	5 to 10 / 3 to 5	7 / 4	Warm-season

Pounds of seed = rate × area ÷ 1,000

Worked example

Seeding a new 2,000 sq ft tall fescue lawn at 8 lb per 1,000 sq ft:

8 × 2,000 ÷ 1,000 = 16 lb of seed
In 5 lb bags: 4 bags

When and how to seed

Cool-season grasses establish best in early autumn, with spring as a second choice; warm-season grasses in late spring to early summer.
Split the seed in half and spread in two directions for even coverage.
Keep the top layer of soil moist (not soggy) until seedlings are established, usually light watering once or twice daily.

FAQ