Grass Seed Calculator
Estimate pounds of seed, bag counts, and contractor quantities for new lawns, overseeding, and repairs using either species guidance or a product label.
Advanced options
Grass Seed Rate Guide
The rate table below is server-rendered on purpose so search engines and low-JS visitors can still see the key seeding logic: new lawns use heavier rates than overseeding, and warm-season bermuda lives on a much lighter scale than cool-season fescues and rye.
Use these rows for planning when you are still choosing a seed family. Once you have a real product, switch to label mode and enter the actual coverage printed on that bag.
| Grass type | New lawn | Overseed | Repair | Notes |
|---|---|---|---|---|
| Kentucky bluegrass Cool-season | 3.5 lb / 1,000 sq ft | 1.5 lb / 1,000 sq ft | 2.5 lb / 1,000 sq ft | 3-4 lb new, 1-2 lb overseed per 1,000 sq ft |
| Tall fescue Cool-season | 6.5 lb / 1,000 sq ft | 4 lb / 1,000 sq ft | 5 lb / 1,000 sq ft | 5-8 lb new, 3-4 lb overseed per 1,000 sq ft |
| Perennial ryegrass Cool-season | 5 lb / 1,000 sq ft | 2.5 lb / 1,000 sq ft | 4 lb / 1,000 sq ft | 4-6 lb new, 2-3 lb overseed per 1,000 sq ft |
| Fine fescue Cool-season | 4.5 lb / 1,000 sq ft | 2.5 lb / 1,000 sq ft | 3.5 lb / 1,000 sq ft | 4-5 lb new, about 2-3 lb overseed per 1,000 sq ft |
| Bermudagrass Warm-season | 1.5 lb / 1,000 sq ft | 0.75 lb / 1,000 sq ft | 1.25 lb / 1,000 sq ft | 1-2 lb new, 0.5-1 lb overseed per 1,000 sq ft |
When Guidance Mode Wins
Guidance mode is best early in the decision: you know the lawn size and whether the job is a new lawn, overseed, or repair, but you have not locked a product yet. It helps you sanity-check pounds and bag sizes before you head to the store.
When Label Mode Wins
Label mode is the right move once you are holding a real bag. Dense-shade mixes, regional blends, and contractor products do not all share one universal rate, so the bag label should override any generic planning estimate.
Species and Planting Window Helper
Region + Exposure Rules of Thumb
Sunny warm-climate lawns: bermuda is usually the first quantity-planning benchmark.
Dense shade: fine fescue or tall fescue are usually safer starting points than bermuda or bluegrass.
Transition-zone lawns: seed choice is less automatic, which is why the calculator treats region as a helper, not a hard blocker.
Planting Windows
| Season | Best window |
|---|---|
| Cool-season grasses | Early fall first, early spring second |
| Warm-season grasses | Late spring through early summer after soil warms up |
How the Math Works
Guidance mode starts with area in thousands of square feet, then multiplies by the selected seeding rate in pounds per 1,000 sq ft. Waste is added after the base pounds so the order plan reflects offcuts, odd lawn shapes, repairs, and a little margin for coming up short.
Label mode skips the agronomic rate and goes straight to the store-facing number: the coverage printed on the bag. The calculator divides your adjusted area by that coverage, rounds up, and then converts the result into pounds only when you also supply the bag weight.
Once pounds are known, the calculator shows 3-, 7-, 20-, and 40-lb bag comparisons, plus a contractor/pallet view for large jobs. Optional blankets and starter fertilizer stay outside the core answer, so they support the order instead of interrupting it.
Worked Example: 2,000 sq ft New Lawn
A homeowner is starting a 2,000 sq ft new lawn and wants a tall-fescue estimate before choosing a store product.
- 1 Project: 2,000 sq ft new lawn
- 2 Grass type: Tall fescue at 6.5 lb per 1,000 sq ft
- 3 Base seed: 2.0 × 6.5 = 13.0 lb
- 4 Add 5% waste: 13.0 × 1.05 = 13.7 lb
- 5 Bag plan: 2 x 7-lb bags or 1 x 20-lb bag
A 5,000 sq ft established lawn is being overseeded to thicken thin spots before fall.
- 1 Project: 5,000 sq ft overseed
- 2 Grass type: Tall fescue at 4.0 lb per 1,000 sq ft
- 3 Base seed: 5.0 × 4.0 = 20.0 lb
- 4 Add 5% waste: 20.0 × 1.05 = 21.0 lb
- 5 Bag plan: 2 x 20-lb bags keeps the order simpler than mixing one 20-lb and one smaller bag
A contractor is pricing a 30,000 sq ft new-lawn seeding job using 40-lb contractor bags.
- 1 Project: 30,000 sq ft new lawn
- 2 Grass type: Tall fescue at 6.5 lb per 1,000 sq ft
- 3 Base seed: 30.0 × 6.5 = 195 lb
- 4 40-lb contractor bags: ceil(195 ÷ 40) = 5 bags
- 5 Pallet view: ceil(5 ÷ 24) = 1 pallet