Enter the size of the lawn, pick the grass and whether you are seeding bare soil or overseeding a thin lawn. The calculator uses the extension seeding rate for that grass, or the rate printed on your seed label, and tells you how many pounds and bags to buy.
How the grass seed calculator works
- Area = lawn length × width.
- Seed = area ÷ 1,000 × seeding rate (lb per 1,000 sq ft).
- Bags = seed ÷ bag size, rounded up.
- For a new lawn the calculator uses the middle of the published range. Choose the label option to use the rate on your bag instead.
Seeding rates by grass type
| Grass | New lawn (lb per 1,000 sq ft) | Overseeding (lb per 1,000 sq ft) |
|---|---|---|
| Turf-type tall fescue | 6 to 8 | 4 |
| Kentucky bluegrass | 2 to 3 | 1.5 |
| Fine fescue | 4 to 5 | 2.5 |
Worked example
A new lawn of 100 × 50 ft is 5,000 sq ft, seeded with tall fescue. At 7 lb per 1,000 sq ft (the middle of 6 to 8), it needs 5 × 7 = 35 lb of seed: seven 5 lb bags. Overseeding the same lawn with Kentucky bluegrass at 1.5 lb per 1,000 sq ft takes 7.5 lb.
Step by step: seeding a lawn
Tips before you buy
- Cool-season grasses are best sown in late summer to early fall; spring is the second choice.
- Seed mixes and coated seed list their own rate on the label; use that.
- More seed is not better: sowing far above the rate makes crowded, weak seedlings.
- For an instant lawn, compare with the sod calculator.
