PROJECT SUMMARY
Grass Seed project summary
Lawn area1500 sq ft
- Job
- New lawn
- Grass
- Tall fescue
- Seed
- 12 lbs @ 8/1,000 sq ft
- Fertilizer
- 2 bags
- Shape
- Rectangular
- Difficulty
- Beginner
- Build time
- ½–1.5 days
- Estimated materials
- $95–$129
Grass Seed Calculator
Pounds of seed by area, grass type and job — new lawn or overseed.
Configure
Grass Seed calculator
Job
Advanced optionsfine-tune the details…
Estimates are planning aids, not a professional quote. Double-check quantities and product coverage — and any local code or permit requirements — before you buy.
⚠ Seed in the right season for your grass: cool-season types (fescue, bluegrass, rye) do best in early fall or spring; warm-season types (bermuda) in late spring to early summer. Seeding in the wrong window is the top reason a new lawn fails.
⚠ Keep the top inch of soil consistently moist — light watering once or twice a day — for the first 2–3 weeks until the grass is established. Letting it dry out even once can kill sprouting seed.
⚠ Do not apply a crabgrass or weed pre-emergent within about 6–8 weeks of seeding — it stops the grass seed from germinating too.
Cost breakdown
Material only · national-average rates
| Soil & Fill | $95–$129 |
| Total | $95–$129 |
Excludes tools, delivery, tax and permit fees. Labor not included — this is a DIY materials estimate.
Shopping list
Every item · grouped by store sectionThese are affiliate links: we may earn a commission if you buy through them, at no extra cost to you. It never changes what the calculator recommends — the shopping list comes from your dimensions, not from what pays.
Soil & Fill
- 12× lbsGrass seed — Tall fescue — 1500 sq ft · 8 lb/1,000 sq ft (new lawn)
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- 2× bagsStarter fertilizer (high-phosphorus) — raked in before seeding to feed new roots
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- 5× 0.75 cu ft bagsTopsoil / compost topdressing (optional) — thin layer to cover seed on bare soil
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Tools
✓ required · ○ helpful
- Broadcast or drop spreader — even seed coverage
- Garden / landscape rake — prep and lightly cover seed
- Lawn roller (rental) — presses seed into contact with soil
- Sprinkler + hose or timer — frequent light watering
- Rototiller or core aerator — loosen compacted soil
Project notes
- Seed is measured by a rate in pounds per 1,000 square feet. A new lawn uses the full rate; overseeding a thin existing lawn uses about half. The calculator applies the right rate for your grass type and job.
- Different grasses seed at very different rates — tall fescue and ryegrass need far more seed per square foot than fine-bladed bluegrass or bermuda. Buy a seed matched to your climate, sun and traffic, not just the cheapest bag.
- Prep matters more than seed brand: loosen compacted soil, rake it smooth, work in a starter fertilizer, and get good seed-to-soil contact by raking lightly and rolling. Seed lying on hard, uncovered soil mostly washes away or feeds the birds.
- This is a seeding calculator, not sod. If you want an instant, established lawn, use the Sod Calculator instead — seeding is cheaper and offers more grass choices, but takes weeks of careful watering to fill in.
About this calculator
How to estimate a grass seed
Enter your lawn's size, the grass type and whether you're seeding a new lawn or overseeding a thin one, and the Grass Seed Calculator tells you exactly how many pounds of seed to buy — at the correct seeding rate for that grass — plus the starter fertilizer and optional straw cover, with a cost estimate.
Different grasses seed at very different rates, and a new lawn needs roughly double the seed of an overseed, so a good estimate saves you from buying way too much or leaving bare patches. Seed in the right season and keep it moist, and the calculator handles the quantities.
Step by step
How to plant grass seed
A step-by-step walkthrough to go with your plan above. Follow the product instructions and any local code or permit requirements as you work.
- 1
Measure and choose seed
Measure the area and pick a grass type suited to your climate, sun and traffic. The calculator turns that into pounds of seed at the right rate for a new lawn or an overseed.
- 2
Prep the soil
Clear weeds and debris, loosen compacted soil by tilling or aerating, and rake the surface smooth and level. Work in a starter fertilizer as you go.
- 3
Spread the seed
Load a broadcast or drop spreader and apply half the seed walking one direction, then the other half at a right angle, for even, gap-free coverage.
- 4
Cover and firm the seed
Rake lightly to just barely cover the seed, then roll or tamp it so it makes firm contact with the soil. Good seed-to-soil contact is what makes seed germinate instead of wash away.
- 5
Mulch if needed
On bare or sloped ground, spread a thin straw or seed-mulch cover to hold moisture and keep the seed from eroding or feeding the birds.
- 6
Water lightly and often
Keep the top inch of soil consistently moist with short, frequent waterings for the first 2–3 weeks. Never let a germinating seedbed dry out.
- 7
Ease into normal care
Once the grass is a few inches tall, taper to deeper, less frequent watering and take the first mow when it's tall enough, removing no more than a third of the blade.
Equip the job
Recommended gear for this build
Hand-picked categories that match the shopping list above. Links open a current selection so you can compare brands and prices.
These are affiliate links: we may earn a commission if you buy through them, at no extra cost to you. It never changes what the calculator recommends — the shopping list comes from your dimensions, not from what pays.
Soil & FillGrass seed (climate-matched blend)Buy a seed suited to your climate, sun and traffic — the blend matters more than the price.
$4–9/lb
ToolsBroadcast / drop spreaderSpreads seed and fertilizer evenly so you don't get thick and bare patches.
$35–70
Soil & FillStarter fertilizerHigh-phosphorus blend raked in before seeding to drive fast, strong rooting.
$18–28/bag
Soil & FillSeed / straw mulchA light cover holds moisture and stops seed washing away on new or sloped ground.
$6–10/bale
ToolsOscillating sprinkler + timerKeeps the seedbed evenly moist through the critical first few weeks.
$20–40
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Answers
Frequently asked questions
How much grass seed do I need?
Multiply your lawn's square footage by the seeding rate for your grass type, then divide by 1,000. A new tall-fescue lawn seeds at about 8 lbs per 1,000 sq ft, so a 1,500 sq ft area needs roughly 12 lbs. Overseeding a thin existing lawn uses about half that. This calculator applies the correct rate for your grass and job automatically.
What's the seeding rate for new lawn vs. overseeding?
A brand-new lawn on bare soil needs the full seeding rate to get complete coverage, while overseeding — spreading seed into an existing thin lawn to thicken it — uses roughly half, since the existing turf fills in the rest. Rates also vary a lot by grass: fine-bladed bluegrass needs far less seed per square foot than coarser fescue or ryegrass.
When is the best time to plant grass seed?
For cool-season grasses (tall fescue, Kentucky bluegrass, ryegrass), early fall is ideal, with spring as the second-best window. Warm-season grasses like bermuda go down in late spring to early summer once the soil is warm. Seeding in the right season — with the right temperatures and moisture — is the single biggest factor in whether a new lawn succeeds.
Should I seed or lay sod?
Seeding is much cheaper, gives you far more grass variety, and works on large areas, but it takes weeks of consistent watering and care before the lawn fills in. Sod gives you an instant, established lawn the day it's laid, at a higher cost and with fewer grass choices. If you want it now, use the Sod Calculator; if you want it affordable, seed.