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Grass seed calculator

Find out how many pounds of grass seed you need for a new lawn or for overseeding, based on your grass type.

Your measurements

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Rates are lb per 1,000 sq ft
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You'll need

Results update as you type.

How much grass seed per square foot?

Seeding rates are given in pounds per 1,000 square feet and depend on the size of the seed. Small seeds like Kentucky bluegrass need only a couple of pounds, while large seeds like tall fescue need much more.

Pounds of seed = Area (sq ft) ÷ 1,000 × seeding rate

Worked example

A new 2,000 sq ft lawn of tall fescue at 7 lb per 1,000 sq ft needs 2 × 7 = 14 lb of seed, or three 5 lb bags.

Seeding rates by grass type

GrassNew lawn (lb / 1,000 sq ft)OverseedingClimate
Tall fescue6–83–5Cool / transition
Kentucky bluegrass2–31–2Cool
Perennial ryegrass5–103–5Cool
Fine fescue3–52Cool, shade
Bermuda (hulled)1–21Warm
Zoysia1–21Warm
Bahia5–103–5Warm
Centipede¼–½¼Warm

The calculator uses the middle of each range. Seed blends list their own rate on the bag, which you should follow.

When to seed

Seed cool-season grasses (fescue, bluegrass, ryegrass) in early fall, when soil is warm and air is cool. Spring is second best. Seed warm-season grasses (Bermuda, zoysia, bahia, centipede) in late spring and early summer.

Tips for a good result

  • Split the seed in half and spread it in two directions, crossways, for even coverage.
  • Rake it in lightly so seed touches the soil, then keep the top inch moist until it sprouts.
  • A thin layer of compost after overseeding helps germination. See the compost calculator.

Frequently asked questions

How much grass seed do I need for 1,000 square feet?

About 6–8 lb of tall fescue, 2–3 lb of Kentucky bluegrass, or 1–2 lb of hulled Bermuda for a new lawn. Overseeding uses roughly half.

How much grass seed for an acre?

An acre is 43,560 sq ft. For a new tall fescue lawn at 7 lb per 1,000 sq ft, that's about 305 lb.

Can I use too much grass seed?

Yes. Over-seeding crowds seedlings so they compete for light and water, which leads to weak, thin grass and more disease.

Last reviewed 2026-11-14. Material weights are typical industry averages and vary by supplier, moisture and compaction.

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