1. Prepare soil
Remove debris, loosen soil and create a firm, level seedbed for good seed-to-soil contact.
Grass Seed Calculator
The right seed. The right rate. A clearer lawn plan.
Lawn Area & Seed Settings
Seed & Bag Coverage Review
TOTAL SEED REQUIREMENT21.48 kgIncludes 10% purchase allowance.
19.53 kgTarget application
(no allowance)
(no allowance)
5 bags5 kg per bag
$175.00Estimated
purchase cost
purchase cost
LAWN APPLICATION PLAN
Two perpendicular spreader passes for even coverage.
39.06 g/m²Application rate
Illustrative rate — not a germination forecast.
1st pass≈9.76 kg
2nd pass≈9.76 kg
Split target application equally; keep allowance in reserve. Displayed halves are rounded.
BAG PURCHASE PLAN
Apply19.53 kgTarget application
Allowance1.95 kg10%
Calculated21.48 kgRequirement
Buy5 × 5 kg=25.00 kg
Above3.52 kgBeyond requirement
Do not spread every purchased bag; extra seed is reserve.
Coverage per bag & full quantity breakdown
| Quantity | Value |
|---|
Package quantities are rounded up to whole bags. Coverage per bag excludes purchase allowance. Tax, shipping and labor are not included.
How the seed plan is calculated
Assumptions & limitations
The visible seeding rate is the actual target used. The species cards are editable examples: tall fescue 8, Kentucky bluegrass 2.5, perennial ryegrass 8 and hulled bermudagrass 1.5 lb per 1,000 sq ft. Rates vary with cultivar, climate, season, label quality and the intended turf. Bermudagrass and zoysia are different grasses.
Overseeding suggests an editable proportion of the full-rate example. Half rate is a planning starting point, not a rule for every species or site. Existing-turf condition and the product label can require a different rate.
Bulk-product mode applies the entered rate directly. PLS mode divides the pure-live target by label purity × germination. Do not automatically apply PLS correction to a label rate that already includes product quality or seed coating. The tool does not predict actual seedling counts or establishment success.
Reserve allowance is separated from the target application. It increases the purchase budget but is not a recommendation to spread all purchased seed. Two-pass quantities are equal before display rounding. Cost uses your price per bag and selected currency label only.
Area-only mode shows an illustrative rectangular layout; its displayed side lengths are a visual assumption, not surveyed dimensions. Rectangle and circle calculations use your actual entered geometry. Paths and beds are subtracted only when explicitly entered.
Frequently asked questions
Is overseeding always half rate?
No. The 50% example is editable. Use the actual species, seed label, turf condition and local extension recommendation; the visible rate is the value used in the calculation.
Does coating change the seed calculation?
It may. Coatings and inert matter affect pure-seed content. Follow the package rate, or use a documented PLS target with label purity and germination. Do not apply both corrections twice.
Should I apply every purchased bag?
No. Apply the calculated target amount. The allowance and whole-bag surplus are stock for losses or later repairs, not an instruction to increase seeding density.
Is this a germination forecast?
No. The illustration and rate bar communicate application planning, not how many seedlings will survive. Soil contact, moisture, temperature and seed quality matter.
Can I use a custom mix?
Yes. Select Custom Seed Mix and enter its label or adviser-agreed rate with the correct rate basis. Mixture composition cannot be inferred from the name alone.
Lawn Care Guide
2. Spread evenly
Use a suitable spreader and two perpendicular passes for uniform coverage.
3. Follow label aftercare
Follow your seed label and local guidance for moisture, timing and establishment care.
Sources & Reference Guides
U.S. Department of AgricultureSeed labels, purity and germination information.
University of Maryland ExtensionHome-lawn seeding rates and renovation guidance.Penn State ExtensionSeed quality and pure-live-seed arithmetic.Additional species references: MU Extension — turfgrass rates · NC State — lawns and bermudagrass. Independent references, not institutional endorsement.
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The right seed. The right rate. A clearer lawn plan.
