How to calculate grass seed
Example: a 5,000 sq ft new lawn of tall fescue at 7 lb per 1,000 sq ft needs 5 × 7 = 35 lb of seed. Overseeding the same lawn needs about 20 lb.
Typical seeding rates
| Grass | New lawn (lb / 1,000 sq ft) | Overseeding |
|---|---|---|
| Tall fescue | 6–8 | 3–5 |
| Kentucky bluegrass | 2–3 | 1–2 |
| Perennial ryegrass | 7–9 | 3–5 |
| Fine fescue | 4–5 | 2–3 |
| Bermudagrass (hulled) | 1–2 | — |
| Zoysiagrass | 1–2 | — |
| Centipedegrass | ¼–½ | — |
Rates are typical ranges published by university extension services; your seed bag's label is the final word, especially for blends and coated seed.
When to seed
Cool-season grasses (fescue, bluegrass, ryegrass) do best seeded in early fall or spring. Warm-season grasses (Bermuda, zoysia, centipede) are best seeded in late spring and early summer once soil is warm.
Frequently asked questions
How much grass seed for 1,000 sq ft?
It depends on the grass: about 7 lb of tall fescue, 2–3 lb of Kentucky bluegrass, or 1–2 lb of Bermudagrass for a new lawn.
How much seed do I need to overseed?
Roughly half the new-lawn rate.
How much grass seed for an acre?
An acre is 43,560 sq ft — about 300 lb of tall fescue for a new lawn, or 110 lb of bluegrass.
Can I put down too much seed?
Yes. Overcrowded seedlings compete for light and water and are more prone to disease. Stick to the label rate.
Related calculators
These figures are estimates for planning only. Material weights and coverage vary by supplier, moisture and compaction. Always confirm quantities and prices with your supplier before ordering. See our terms & disclaimer.