Quick checks
•
Match seed rate to the seeding goal, not just area size
Free Grass Seed Calculator
Estimate seed pounds, bags, and cost for new lawns, overseeding, and patch repair.
Lbs & Bags
Seed Rate by Type
Cost Estimate
Grass Seed Calculator
Quick tools
Set units once. Reopen recent results anytime.
Scenario presets
Pick the seeding job
Use a new lawn, overseeding, or patch repair preset.
Quick checks
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Check soil temperature and season before buying seed
Quick checks
•
Plan watering schedule before spreading
Seeding planning
Choose the seeding goal before you buy seed
New lawns, overseeding, and patch repair all use different seed rates and timing.
New lawn from bare soil
Use the highest seed rate and plan for consistent watering during germination.
Bare soil needs full coverage. Skimping on seed leads to thin patches and weed invasion.
Aerate or rake the soil first for good seed-to-soil contact.
Overseeding existing lawn
Use half the new-lawn rate and focus on thin or bare areas.
Overseeding thickens turf but cannot establish well if the existing grass is too dense. Mow short first.
Aerate or dethatch so seed reaches the soil instead of sitting on blades.
Patch repair
Use a mid-range rate and prepare each patch individually.
Patch repair is faster than full seeding but still needs loosened soil and steady moisture.
Rake each patch to bare soil, spread seed, and cover lightly with compost or peat moss.
Fast planning rules
Start with the seeding rules that change the order
Check seed rate, timing, and soil prep before you buy.
Seed rate for new lawn
New lawns typically need 6 to 10 pounds of seed per 1,000 square feet depending on grass species.
Cool-season grasses like fescue and bluegrass often need higher rates than warm-season grasses.
Overseeding vs. new lawn
Overseeding uses about half the seed rate of a new lawn because grass already covers much of the soil.
Typical overseeding rate is 2-5 lbs per 1,000 sq ft vs. 6-10 lbs for a new lawn.
Best time to seed
Early fall is ideal for cool-season grasses. Late spring to early summer works for warm-season grasses.
Soil temperature and moisture matter more than air temperature for germination.
What is a grass seed calculator? It turns lawn dimensions into seed pounds, bag count, and cost based on your seeding goal—new lawn, overseeding, or patch repair.
How to Calculate Grass Seed for Your Lawn
Use this calculator to estimate grass seed for any lawn project. Enter dimensions, choose seeding type, set seed rate, and optional bag pricing for a complete material list.
Understanding Seed Rates
Seed rate is measured in pounds per 1,000 square feet. The right rate depends on your goal:
- New lawn: 6-10 lbs / 1,000 sq ft (full coverage on bare soil)
- Overseeding: 2-5 lbs / 1,000 sq ft (thickening existing grass)
- Patch repair: 4-8 lbs / 1,000 sq ft (filling bare spots)
Seed Rate by Grass Type
| Grass Type | New Lawn | Overseeding |
|---|---|---|
| Kentucky Bluegrass | 3-4 lbs / 1k sq ft | 1.5-2 lbs / 1k sq ft |
| Tall Fescue | 8-10 lbs / 1k sq ft | 4-5 lbs / 1k sq ft |
| Perennial Ryegrass | 6-9 lbs / 1k sq ft | 3-5 lbs / 1k sq ft |
| Fine Fescue | 4-5 lbs / 1k sq ft | 2-3 lbs / 1k sq ft |
| Bermuda | 1-2 lbs / 1k sq ft | 0.5-1 lb / 1k sq ft |
Seeding Timing Guide
Cool-Season Grasses (Fescue, Bluegrass, Ryegrass)
- Best: Early fall (mid-August to mid-October)
- Good: Early spring (March to April)
- Avoid: Summer heat and mid-summer drought
Warm-Season Grasses (Bermuda, Zoysia, St. Augustine)
- Best: Late spring to early summer (May to June)
- Good: Early summer when soil is warm
- Avoid: Fall and winter when soil cools
2025 Grass Seed Cost Guide
Seed prices vary by species, blend quality, and brand. Here is what to expect in 2025:
Seed Costs per Pound
| Grass Type | Price per Pound |
|---|---|
| Tall Fescue | $2.50–4.50 |
| Kentucky Bluegrass | $4.00–7.00 |
| Perennial Ryegrass | $2.00–4.00 |
| Fine Fescue | $3.50–6.00 |
| Bermuda | $10.00–20.00 (hulled) |
Tips for Successful Seeding
- Test your soil first. A soil test reveals pH and nutrient needs.
- Loosen the top layer. Rake or aerate so seed makes contact with soil.
- Spread evenly. Use a broadcast spreader and apply in two directions.
- Water lightly and often. Keep the top 1/4 inch moist until germination.
- Wait to mow. Let grass reach 3-4 inches before the first cut.
How we checked this page
Written by: TheSiteMath Editorial Team
Reviewed by: TheSiteMath editors (formula, source, and update review)
Last reviewed: 2026-03-20
Publisher:
TheSiteMath
Scope: U.S. construction material estimating, calculator workflows, and project planning guidance for contractors and homeowners.
What we checked:
- • Formulas checked against trade and source material
- • Verified against: Landscape material coverage and delivery references, Supplier tonnage / cubic-yard conversion assumptions, Current U.S. landscaping material pricing benchmarks
- • Price ranges used for planning, not as fixed quotes
- • Examples checked in the live calculator
Methodology:
- • Example quantities and explanations on this page are cross-checked against the matching live calculator on TheSiteMath.
- • This landscaping content is scoped for U.S. planning and estimating workflows, not for stamped engineering or permit approval.
- • We review formulas, material assumptions, and practical steps against category-appropriate references before publishing updates.
- • We refresh pages when calculator logic, supplier assumptions, or pricing guidance materially changes.
- • Readers should confirm final dimensions, structural requirements, and local code obligations with qualified local professionals.
Editorial standards: We review pages before publication and update them when formulas or pricing need a fix. If you spot an issue, please
contact us
.
For our review process, corrections policy, and monetization disclosure, see the Editorial Standards page.
Grass Seed FAQ
Seed rate and timing questions before you spread
These questions focus on pounds per 1,000 sq ft, seeding type, and germination timing so the lawn establishes properly.
How much grass seed do I need per 1,000 square feet?
For a new lawn: 6-10 lbs per 1,000 sq ft depending on grass type. For overseeding: 2-5 lbs per 1,000 sq ft. For patch repair: 4-8 lbs per 1,000 sq ft. Kentucky bluegrass needs 3-4 lbs per 1,000 sq ft because its seeds are small and numerous. Tall fescue needs 8-10 lbs per 1,000 sq ft due to larger seeds.
How much does grass seed cost in 2025?
In 2025, quality grass seed costs $3.00-6.00 per pound for common varieties. A 25-lb bag of tall fescue costs $50-90. A 10-lb bag of Kentucky bluegrass mix costs $40-70. Premium blends with improved cultivars cost 20-40% more. Bulk seed from landscape suppliers can be cheaper than retail bags.
Should I use a seed spreader or hand-broadcast?
A broadcast spreader is recommended for areas over 500 sq ft because it distributes seed evenly. Hand-broadcasting works for small patches but often leads to clumping and uneven coverage. For best results, divide your seed in half and spread in two perpendicular directions. This cross-hatch pattern ensures even coverage.
Do I need to put topsoil over grass seed?
You do not need a thick topsoil layer. Rake seed into the top 1/4 inch of soil for good contact. A light dusting of peat moss or screened compost helps retain moisture. Avoid burying seed deeper than 1/2 inch—most grass seeds need light to germinate. For overseeding, aerate first so seed falls into the holes.
How long does it take grass seed to germinate?
Germination times vary by grass type: Perennial ryegrass germinates in 5-10 days. Tall fescue in 7-14 days. Kentucky bluegrass in 14-21 days. Bermuda grass in 7-14 days when soil is warm. Zoysia grass in 14-21 days. Keep soil consistently moist during germination. Dry spells of even a day can kill young seedlings.
Can I overseed an existing lawn?
Yes. Mow the existing grass short (1.5-2 inches), aerate or dethatch to expose soil, spread seed at the overseeding rate, and water lightly twice daily for 2-3 weeks. Fall is the best time to overseed cool-season lawns. Spring works too, but summer heat stress can damage young grass. Avoid overseeding during drought or extreme temperatures.
What is the difference between coated and uncoated seed?
Coated seed has a clay or polymer coating that improves moisture retention, nutrient availability, and bird deterrence. Coated seed requires about 30-50% more weight per area because the coating adds bulk. Uncoated seed is pure seed and often cheaper per pound of actual seed. For best value, compare pure live seed (PLS) percentages rather than bag weight alone.