How Much Do I Need?

Grass Seed and Sod Calculator

How much grass seed or sod do I need?

Enter the size of the lawn and choose seed or sod. For seed, use the seeding rate on the bag. For sod, use the size of one roll. The calculator adds a margin and rounds up to bags, rolls or pallets.

Units
Lawn area

For L-shaped or irregular spaces, split them into rectangles and add each one.

Seed or sod

From the bag, and it varies a lot by grass type. Overseeding an existing lawn usually uses about half the new-lawn rate.

For edges, curves and cuts (sod) or uneven spreading (seed).

Cost (optional)

Add the price to see an estimated total.

Results update as you type.

Your estimate

Grass seed to buy

2 bags

5 lb bags: 6.3 lb of seed for 1,000 ft², including 5% extra.

Estimated amount to buy

Bags (5 lb each)
2
Seed with 5% extra
6.3 lb

Calculated quantity (no extra)

Lawn area
1,000 ft²
Seed
6 lb (2.72 kg)
How this was calculated
  1. Lawn area = 40 ft × 25 ft = 1,000 ft²
  2. Seed = 1,000 ft² × 6 lb per 1,000 ft² = 6 lb
  3. With 5% extra = 6 lb × 1.05 = 6.3 lb
  4. Bags = 6.3 lb ÷ 5 lb = 1.26, rounded up to 2
  • Seeding rates differ widely between grass types, so the rate on your bag matters more than anything else here.

How the seed and sod calculation works

  1. Lawn area = length × width. Add more rectangles for L-shaped or irregular lawns.
  2. Seed = area × seeding rate, plus the extra. Bags = seed ÷ bag size, rounded up.
  3. Sod: area plus the extra, ÷ the area of one roll, rounded up. Pallets are worked out the same way.

Rates are converted exactly: 1 lb per 1,000 ft² is about 4.9 g per m².

Seeding rates

How much seed to sow depends mostly on the grass. Fine, small-seeded grasses such as Kentucky bluegrass are sown at low rates (often around 2–3 lb per 1,000 ft²), while coarser grasses such as tall fescue need more (often around 6–8 lb). Mixes fall in between. Overseeding a thin lawn typically uses about half the new-lawn rate. Always follow the rate printed on your bag. The default of 6 lb per 1,000 ft² (about 30 g per m²) is only a starting point.

Rounding rules

  • Bags, rolls and pallets are rounded up after the extra is added.
  • The exact seed weight or roll count, before extra and rounding, is shown separately.