Grass Seed Calculator

sq ft
Biology

Calculate how many pounds of grass seed you need to seed or overseed your lawn.

Formula

Seed (lbs) = (Area ÷ 1000) × seeding rate (lbs/1000 sq ft)
  • New lawn seeding uses full rate; overseeding uses half rate.
  • Add 10% extra for irregular areas and germination losses.
  • Best germination temperatures: cool-season grasses 60–65°F soil; warm-season 70–90°F.

500 sq ft new lawn, tall fescue

Inputs
  • Lawn Area: 500 sq ft
  • Grass Type: tall_fescue
  • Seeding Type: new

(500 ÷ 1000) × 8 = 4 lbs of tall fescue seed.

Frequently asked questions

When is the best time to seed?
Cool-season grasses: late summer to fall. Warm-season grasses: late spring to early summer.
Should I buy more than calculated?
Yes, purchase 10–15% extra to account for uneven spreading and germination failures.