Grass Seed Calculator — How Much Seed Do You Need?
Enter your lawn size and grass type, and choose new lawn or overseeding, to get how much grass seed you need in pounds and bags.
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How it works
lbs = (length × width ÷ 1000) × rate; rate = grass-type rate × mode factor
Seeding rate by grass type (lbs per 1,000 sq ft)
| Grass type | New lawn | Overseeding |
|---|---|---|
| Tall fescue | 8 lb | 4 lb |
| Perennial ryegrass | 7 lb | 3.5 lb |
| Fine fescue | 5 lb | 2.5 lb |
| Kentucky bluegrass | 3 lb | 1.5 lb |
| Bermuda | 2 lb | 1 lb |
Rates are typical starting points — always check your seed label, since blends vary. Overseeding an existing lawn uses about half the new-lawn rate.
Frequently asked questions
How much grass seed do I need per 1,000 square feet?
It depends on the grass: a new lawn needs about 8 lb of tall fescue, 7 lb of perennial ryegrass, 3 lb of Kentucky bluegrass, or 2 lb of Bermuda per 1,000 sq ft. Overseeding uses about half those amounts.
How much seed do I need to overseed 5,000 sq ft?
Overseeding 5,000 sq ft of tall fescue at about 4 lb per 1,000 sq ft takes roughly 20 lb of seed. For perennial ryegrass (~3.5 lb) it is about 17.5 lb, and for Kentucky bluegrass (~1.5 lb) about 7.5 lb.
How much grass seed do I need per acre?
An acre is 43,560 sq ft. A new tall-fescue lawn at 8 lb per 1,000 sq ft needs about 350 lb per acre; Kentucky bluegrass runs about 130 lb and Bermuda about 87 lb per acre. Overseeding needs roughly half.