Grass Seed Calculator
Estimate how much grass seed you need by area and depth — plus bags and total cost. Switch between imperial and metric units.
Grass Seed Calculator
Estimate how much you need — and the cost.
- sq meters 9.29
Quick coverage reference
Seeding rate depends on grass type — a new lawn needs roughly 1 lb of seed per 200–250 sq ft, overseeding about half that. Pounds = lawn area ÷ coverage per lb.
How it's calculated
Source: inchcalculator.com/grass-seed-calculator/ (new-lawn vs overseed rates cross-checked)
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</script>How much grass seed do I need?
Grass seed is bought by the pound, and how much you need depends on the seeding rate for your grass type. A new lawn typically needs about 1 lb of seed per 200–250 sq ft; overseeding an existing lawn uses roughly half that.
Use pounds = lawn area (sq ft) ÷ coverage per lb. At 250 sq ft per pound, a 1,000 sq ft lawn needs about 4 lb for new seeding, or about 2 lb to overseed. Rates vary by species — fine fescue spreads further than ryegrass — so enter the coverage from your seed bag for the most accurate amount.
How to measure for grass seed
Measure the lawn
Length × width of each area in feet. Break curved or irregular lawns into rectangles and circles and total them.
Choose new vs. overseed
New lawns need the full rate (about 1 lb per 200–250 sq ft); overseeding an established lawn needs roughly half.
Enter the seeding rate
Read the coverage per pound off the seed bag for your grass type and enter it — rates vary by species.
Read pounds needed
The calculator returns the pounds of seed to buy. Add a little extra for edges and re-seeding thin spots.
Grass seed buying tips
Fine fescues cover more ground per pound than ryegrass or bluegrass. Always use the rate on your specific seed bag.
Bare soil needs the full rate for good cover; overseeding a living lawn needs about half to avoid crowding.
Seed-to-soil contact drives germination. Loosen and rake the surface first, and keep it moist until the grass establishes.
Grass seed calculator FAQ
How much grass seed do I need per square foot?
For a new lawn, roughly 1 lb per 200–250 sq ft. Overseeding an existing lawn needs about half that rate.
How much seed for a 1000 sq ft lawn?
About 4 lb for new seeding at 250 sq ft per pound, or roughly 2 lb to overseed. Check your seed bag for the exact rate.
Does the seeding rate depend on grass type?
Yes. Fine fescue spreads further per pound than ryegrass or bluegrass, so always use the rate printed on the bag.
What is the difference between seeding and overseeding?
Seeding is starting a lawn on bare soil at the full rate; overseeding thickens an existing lawn at about half the rate.
Should I buy extra grass seed?
A little. Keep some spare for edges and to re-seed any thin or bare spots after the first germination.