Grass Seed Calculator
Estimate grass seed requirements for new lawns, overseeding, and patch repair using area and seed rate.
96 m²
3,360 g
3.36 kg
2,880-3,840 g
How the calculator works
The calculator multiplies lawn area by seed rate in grams per square metre. You can either enter length and width or override with a known area.
Default rates are 35 g/m² for a new lawn and 20 g/m² for overseeding, but the rate remains editable for your seed blend.
Frequently asked questions
How much grass seed do I need per square metre?
Typical rates are around 35 g/m² for a new lawn and about 20 g/m² for overseeding. Product labels can vary, so check the pack.
What is the difference between seeding and overseeding?
Seeding establishes a new lawn from bare soil. Overseeding adds seed into an existing lawn to improve density or repair thin patches.
When is the best time to sow grass seed?
Spring and early autumn are usually best, when soil is moist and temperatures support fast germination.
Should I buy extra grass seed?
Buying a small surplus is sensible for patch repairs and uneven spread. Around 5 to 10% extra is common.