Grass Seed Calculator: How Much Seed Do I Need?
Enter your lawn size and grass type and we'll tell you exactly how many pounds of seed to buy — for a new lawn or for overseeding — plus the best window to plant. Seeding rates follow standard agronomic guidelines.
Top-rated grass seed
Genuinely good, Amazon-available picks.
Pennington Smart Seed Sun & Shade
Beginner friendlyPennington Annual Ryegrass (Bulk)
Beginner friendlyPennington Smart Seed Dense Shade
Beginner friendlyPennington Kentucky 31 Tall Fescue
Beginner friendlyAs an Amazon Associate, Measure Lawn earns from qualifying purchases.
Spreaders for even coverage
Chapin 8401C International Chest-Mount Spreader
Beginner friendlyRecommended for lawns under 5,000 sq ft. Hands-free chest-mount design for easy spreading of fertilizer seed and granular products.
Scotts Turf Builder Classic Drop Spreader
Beginner friendlyAs an Amazon Associate, Measure Lawn earns from qualifying purchases.
How much grass seed per square foot?
Grass seed is measured in pounds per 1,000 square feet, and every grass is different — a fine, spreading grass like Bermuda needs far less seed than a coarse, bunch-type grass like tall fescue. The other big factor is the job: seeding a new lawn on bare soil takes about twice as much seed as overseedingan existing thin lawn, because established grass fills in the gaps.
| Grass type | New lawn (lb/1,000 sq ft) | Overseeding |
|---|---|---|
| Tall Fescue | 6–10 | 3–5 |
| Kentucky Bluegrass | 2–3 | 1–2 |
| Perennial Ryegrass | 6–10 | 3–5 |
| Fine Fescue | 4–5 | 2–3 |
| Bermuda (hulled) | 1–2 | 0.5–1 |
| Zoysia | 1–2 | 0.5–1 |
Measure your real lawn free on satellite imagery in 2 minutes — then your seed total is exact, with no waste.
Measure my lawn free →Grass seed questions, answered
How much grass seed do I need per 1,000 sq ft?
It depends on the grass and whether you are starting a new lawn or overseeding. Typical new-lawn rates per 1,000 sq ft: tall fescue 6–10 lb, Kentucky bluegrass 2–3 lb, perennial ryegrass 6–10 lb, fine fescue 4–5 lb, Bermuda 1–2 lb (hulled), zoysia 1–2 lb. Overseeding an existing lawn uses about half the new-lawn rate.
How much grass seed for overseeding?
About half the new-lawn rate. If a new tall-fescue lawn needs ~8 lb per 1,000 sq ft, overseed at ~4 lb. Overseeding into a thin existing lawn does not need full coverage because the established grass fills in.
What happens if I use too much or too little seed?
Too little leaves bare patches that weeds invade. Too much makes seedlings compete for water and nutrients, so they grow thin and weak and are prone to disease. Staying in the recommended range gives the thickest, healthiest lawn.
When is the best time to plant grass seed?
Cool-season grasses (fescue, bluegrass, ryegrass) seed best in early fall (about Sep 1 – Oct 15), with spring as a backup. Warm-season grasses (Bermuda, zoysia) seed best in late spring to early summer once soil is reliably warm. The calculator shows the window for your selected grass.