Lawn
Grass Seed & Overseeding Calculator — Sq Ft or Acres
Enter lawn dimensions or a known area in square feet or acres, then use the new-lawn or overseeding rate printed on your seed product label.
Estimated grass seed
0.88 lb of seed200 square feet0.0046 acres0.8 lb before the buffer- 1 bag at 3 lb
- Rate entered: 4 lb per 1,000 sq ft
Formula
lawn area in square feet ÷ 1,000 × label rate = pounds of seed; for acres: 43.56 × label rate in lb / 1,000 sq ft = pounds per acre
Grass seed answers by square feet or acres
For 1 acre, the calculator converts 43,560 square feet before applying the label rate. At 4 lb per 1,000 sq ft, that is 174.24 lb before buffer. For a 5,000 sq ft overseeding project at the same example rate, it is 20 lb before buffer. Replace the example rate with the exact rate for your seed and project.
New lawn vs. overseeding seed rate
Choose New lawn for bare-soil establishment or Overseeding for adding seed to existing turf. The selection clarifies the project but never changes the rate automatically because grass species, seed blends, climate, season, and local conditions affect the correct amount.
- Enter the new-lawn rate printed on the product label when establishing bare soil.
- Enter the overseeding rate printed on the product label when adding seed to existing turf.
- Use local Extension guidance when the label or local growing conditions call for additional context.
How many bags of grass seed should I buy?
The calculator divides the seed pounds including your buffer by the bag weight and rounds up to a whole bag. A small buffer can help with irregular edges, but it is not a substitute for the correct product-label rate.
Sources and guidance
Use these references for unit conversion and lawn-seeding context, then follow the selected product label and local Extension guidance for your project.
Quick reference
| Project size | Common use | Planning note |
|---|---|---|
| 1 acre at 4 lb / 1,000 sq ft | New lawn or overseeding example | 43,560 sq ft requires 174.24 lb before buffer; use 4 lb only when it matches the selected product label. |
| 5,000 sq ft overseeding | Existing lawn | At an example label rate of 4 lb per 1,000 sq ft, the result is 20 lb before buffer. |
| 1,000 sq ft lawn | Small new lawn or overseeding project | The pounds needed equal the label rate before buffer; do not automatically halve a new-lawn rate for overseeding. |
FAQ
How much grass seed do I need for one acre?
One acre is exactly 43,560 square feet. Divide by 1,000 and multiply by the rate printed on your product label. At 4 lb per 1,000 square feet, one acre needs 174.24 lb before buffer.
Should I use a new-lawn or overseeding seed rate?
Use the rate the product label gives for the chosen project. Do not blindly halve a new-lawn rate: overseeding guidance depends on the seed blend, existing turf, and local growing conditions.
Can I enter acres instead of lawn dimensions?
Yes. Choose Direct area and Acres. The calculator uses the exact conversion of 1 acre to 43,560 square feet before applying your label rate.