Grass Seed Calculator
How much grass seed a new or overseeded lawn needs, and how many bags to buy.
Every calculation runs locally in your browser. Seeding rate is printed on the product label and varies by grass type and whether you're seeding bare soil or overseeding an existing lawn.
Bags to buy
1
Total seed needed
3.5 kg
For informational and educational purposes only — not professional advice, and not a substitute for consulting a qualified professional about your specific situation. TrueMeasureKit is not liable for decisions made based on these results. See our Terms of Service.
Why new lawns need a much heavier rate than overseeding
Seeding bare soil from scratch needs enough seed density to fully establish coverage on its own, while overseeding an existing lawn only needs to fill in thin or bare patches among grass that's already there — product labels usually list both rates separately, and using the new-lawn rate when overseeding wastes seed that will mostly land on ground already covered.
Frequently asked questions
Does overseeding need a different seeding rate than a new lawn?
Yes — a bare new lawn typically needs a higher seeding rate than overseeding an existing lawn, since overseeding is filling in gaps rather than establishing coverage from scratch. Check your specific seed product's recommended rate for each scenario.