Calculate grass seed pounds needed by area and seed type.
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Usage Tip
Split the seed into two passes at right angles for even coverage, and keep the top inch of soil moist until it germinates.
Overseeding an existing lawn uses about half the rate of seeding bare ground.
How much grass seed do I need?
Grass seed is sold by the pound and applied at a rate per 1,000 sq ft, so the seed you need is your area divided by 1,000, times the rate for your grass. The catch is that the rate roughly doubles between overseeding an existing lawn and starting a new one from bare soil. A 5,000 sq ft new lawn of tall fescue at 8 lb per 1,000 needs about 40 lb; overseeding the same lawn at 4 lb needs only 20. This calculator picks the rate from your grass type and scenario, adjusts for germination and waste, and works out bags and cost.
Grass seed rate chart
Seeding rates in pounds per 1,000 sq ft, new lawn versus overseeding:
| Grass type | New lawn | Overseed |
|---|---|---|
| Kentucky bluegrass | 2 to 3 | 1 to 1.5 |
| Perennial ryegrass | 6 to 9 | 4 to 5 |
| Tall fescue | 6 to 10 | 4 to 6 |
| Bermuda | 1 to 2 | 0.5 to 1 |
| Zoysia | 1 to 2 | 0.5 to 1 |
| Fine fescue | 4 to 5 | 2 to 3 |
Seed coverage chart
How far a pound of seed goes depends on the rate. At common new-lawn rates:
| Lawn size | Tall fescue (8 lb/1k) | Bluegrass (3 lb/1k) |
|---|---|---|
| 1,000 sq ft | 8 lb | 3 lb |
| 5,000 sq ft | 40 lb | 15 lb |
| 10,000 sq ft | 80 lb | 30 lb |
| 1 acre (43,560 sq ft) | about 350 lb | about 130 lb |
Overseeding rate vs new lawn rate
The single most common seeding mistake is using a new-lawn rate to overseed, or the reverse. Overseeding thickens an existing lawn, so you need roughly half the seed — the established turf does most of the work. A new lawn or a bare patch has no competition and no cover, so it needs the full rate to get dense before weeds move in. Bare-spot repair uses the new-lawn rate because you are establishing from scratch on a small scale.
Seasonal planting window
Timing is half the battle. Cool-season grasses (bluegrass, ryegrass, fescue) go down best in early fall, with early spring as a second choice. Warm-season grasses (bermuda, zoysia) want late spring to early summer once the soil has warmed.
| Grass | Best window |
|---|---|
| Cool-season (bluegrass, rye, fescue) | Early fall, then early spring |
| Warm-season (bermuda, zoysia) | Late spring to early summer |
Watering new grass seed
New seed must stay consistently moist until it germinates. Water lightly two or three times a day for the first couple of weeks, keeping the top inch damp but not soggy, then taper to deeper, less frequent watering as the grass fills in. Straw or seed mulch helps hold that moisture, especially on slopes.
Frequently asked questions
How much grass seed per 1,000 sq ft?
Roughly 2 to 3 lb for bluegrass, 6 to 9 lb for ryegrass or tall fescue, at new-lawn rates. Halve those for overseeding.
What is the difference between overseeding and new lawn rates?
Overseeding uses about half the seed of a new lawn, because the existing turf already provides cover and competition.
When is the best time to plant grass seed?
Early fall for cool-season grasses, late spring to early summer for warm-season grasses.
Does germination rate matter?
Yes. If your seed germinates below the label rate, increase the amount to compensate. The calculator adjusts for this.
How much seed for a bare spot?
Use the new-lawn rate, since you are establishing grass from bare soil. The calculator does this in bare-spot mode.
Do I need starter fertilizer and straw?
Starter fertilizer helps new seed root, and straw or seed mulch holds moisture. The calculator estimates both from your area.
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Estimates are for planning. Seeding rates vary by seed blend, soil prep and climate; always check the rate on your seed bag and follow local timing. Buy a little extra for waste and touch-ups.