GRASS SEED
Grass seed calculator
Pounds of seed = (area in square feet ÷ 1,000) × the seeding rate for your species. The rate is the only input this page will not choose for you, because it belongs to the grass you are sowing and to whether you are starting a lawn or overseeding one. What this page does is show the arithmetic, and cite the rates published by extension services so you can see the shape of the answer.
Worked example
A 6,000 sq ft lawn, overseeding, at 4 pounds per 1,000 square feet: 6,000 ÷ 1,000 = 6, and 6 × 4 = 24 pounds of seed.
That is the whole calculation. The rest of this page is about where the rate comes from and why it varies so much.
Published rates, with their sources
These are figures published by extension services for named species and named jobs. They are quoted as their figures, attributed below — not as a recommendation for your lawn, because the right rate depends on your species, your region, your seed's germination and purity, and whether you are establishing or overseeding.
| Species and job | Rate as published | Source |
|---|---|---|
| Tall fescue, establishment | 5 to 6 pounds per 1,000 sq ft | University of Georgia Extension, Fannin-Gilmer County |
| Tall fescue blend | 8-10 pounds per 1,000 sq ft | University of Arkansas Extension, FSA-6118 |
| Perennial ryegrass, home lawns (winter overseeding) | 8-10 pounds per 1,000 sq ft | Mississippi State University Extension, Turf Tips |
| Annual ryegrass, same job | Add a further 2 pounds per 1,000 sq ft | Mississippi State University Extension, Turf Tips |
The spread is the point: the same species carries two different published rates depending on which state's guidance you read, and ryegrass carries a third. Your own seed label or your own state extension service is the figure that fits your lawn.
Overseeding is not the same as establishing
Georgia Extension gives a method rather than a second table for this: estimate the percentage of the stand you have lost and multiply it by the establishment rate. Their worked example is quoted below. The arithmetic is the same shape as anything else on this site — work out the whole-lawn rate first, then scale it by the fraction you are actually replanting.
So a lawn that is half gone, at an establishment rate of 6 pounds per 1,000 sq ft, is 0.5 × 6 = 3 pounds per 1,000 sq ft over the whole area. Do the scaling before you multiply by area, or the rounding will cost you a bag.
Measure the area the same way every time
- Rectangle:
length × width - Circle:
π × radius² - Triangle:
base × height ÷ 2
Add the shapes, subtract beds, paths, the drive and the ground under shrubs. On a full overseed you seed over the existing grass, so nothing comes off; on a repair patch, measure the patch on its own and use the repair rate.
Coverage per pound
Turned around, the same rate answers how far a pound goes: square feet per pound = 1,000 ÷ the rate per 1,000 sq ft. At 5 lb per 1,000 sq ft, one pound covers 1,000 ÷ 5 = 200 sq ft. At 8 lb per 1,000 sq ft, one pound covers 125 sq ft. The higher the rate, the less ground a pound covers — which is the quickest way to see why comparing seed by price per pound across species tells you very little.
It is also the check to run against a bag that claims a coverage figure. A stated coverage implies a rate: covering 1,000 sq ft with 5 lb is a rate of 5 lb per 1,000 sq ft, and you can compare that with the rate your own extension service publishes for that species.
Using this as an overseeding calculator
For an overseed rather than a new lawn the calculation is the same shape with a lower rate. There are two arithmetic routes: use the overseeding rate your label or extension service publishes, or start from the establishment rate and scale it by the fraction of the stand you have lost. Georgia Extension gives the second method, quoted with its source below.
Worked: 4,000 sq ft, establishment rate 6 lb per 1,000 sq ft, half the stand lost — 4,000 ÷ 1,000 = 4; 0.5 × 6 = 3 lb per 1,000 sq ft; 4 × 3 = 12 lb. Running the establishment rate without the loss fraction would have ordered 24 lb, twice what the job needs.
A lawn that is only patchy is usually better measured patch by patch at the repair rate than scaled across the whole area, because the fraction-lost method assumes the loss is spread evenly.
What actually decides whether the seed becomes lawn
None of it is the bag count. Seed-to-soil contact matters most — seed sitting on thatch germinates poorly however much you bought — followed by covering the seed lightly, keeping the surface moist until germination, and sowing inside the window for your grass type. Buying the right weight and then leaving it on top of the thatch is the commonest way to waste the whole calculation.
Related calculators
How much grass seed do I need for the same arithmetic with a step-by-step layout · Sod calculator if you are laying turf instead · How many square feet in a pallet of sod for the turf equivalent.
Sources, all read directly on 2026-09-21: University of Georgia Extension (Fannin-Gilmer County), “Early fall is ideal for seeding tall fescue lawns”, site.extension.uga.edu — “The ideal seeding rate for tall fescue is 5 to 6 pounds per 1,000 square feet”, and “If the lawn needs reseeding, estimate the percentage of tall fescue loss and multiply that number by the establishment seeding rate of 6 pounds per 1,000 square feet”, with the example “if 50 percent (0.5) of the stand is lost, reseed with 0.5 x 6 = 3 pounds per 1,000 square feet”. University of Arkansas Extension, FSA-6118, uaex.uada.edu — “Use a blend of tall fescue cultivars at 8-10 pounds per thousand square feet” (the PDF text extraction drops the hyphen; the figure is 8 to 10). Mississippi State University Extension, Turf Tips newsletter, extension.msstate.edu — “Seeding rate for home lawns with perennial ryegrass should be 8-10 pounds per thousand square feet and if you use annual ryegrass increase this by another 2 pounds.”
Cite this dataset
The mulch coverage, bag-count and dated price tables from this site are archived as a citable dataset: Mulch coverage, bag-count and dated bulk price tables, version v1, published 20 September 2026, 9 files, creator ERTHK — DOI 10.5281/zenodo.22855990, record at zenodo.org/records/22855990.
Released under CC0 1.0 Universal (Creative Commons Zero v1.0 Universal): free to copy, modify and redistribute.
The source library that generates the tables, with its test suite, is at github.com/ERTHK/mulch-measure-calculator-kit, released under the MIT license.