Seed Rate Calculator
Maize sown at 60 × 20 cm, one seed per hill, with a 300 g test weight, 90 % germination and 98 % purity needs 28.3447 kg/ha.
Maize 250–350 g, wheat 35–45 g, soybean 100–150 g, paddy 20–30 g.
28.3446712018141 kg/ha
Full answer, then cut to fewer decimals (not rounded):
- 28.3446712018141 kg/ha
- 28.344671201814 kg/ha
- 28.34467120181 kg/ha
- 28.3446712018 kg/ha
- 28.344671201 kg/ha
- 28.34467120 kg/ha
- 28.3446712 kg/ha
- 28.344671 kg/ha
- 28.34467 kg/ha
- 28.3446 kg/ha
- 28.344 kg/ha
- 28.34 kg/ha
- 28.3 kg/ha
- Plant population
- 83333.33333 plants/ha
- Seed rate before correction
- 25 kg/ha
- Pure live seed fraction
- 88.2 %
Step-by-step solution
- Plants/ha = 10,000 ÷ (0.6 × 0.2) = 83333.33333
- Seed = plants × seeds/hill × test weight ÷ 10⁶ = 25 kg/ha
- Corrected = 25 ÷ (0.9 × 0.98) = 28.3446712 kg/ha
Seed Rate Formula
Seed rate = (10⁴/(row × plant spacing)) × seeds/hill × test weight / (10⁶ × germination × purity)
spacings in m, test weight in g per 1000 seeds
Worked Example
Maize at 60 × 20 cm, one seed per hill, 300 g test weight, 90 % germination, 98 % purity:
- Plants/ha = 10,000 ÷ (0.6 × 0.2) = 83333.33333
- Seed = plants × seeds/hill × test weight ÷ 10⁶ = 25 kg/ha
- Corrected = 25 ÷ (0.9 × 0.98) = 28.3446712 kg/ha
Seed rate before correction: 25 kg/ha · Pure live seed fraction: 88.2 %
GATE tip
Keep spacings in metres: 60 × 20 cm is 0.12 m² per hill, so 83,333 hills per hectare.
More Crop Inputs Calculators
-
Fertilizer Requirement Calculator
DAP = P₂O₅/0.46; urea = (N − 0.18 DAP)/0.46; MOP = K₂O/0.60
SSP = P₂O₅/0.16 when SSP supplies phosphorus
Example: A 120:60:40 kg/ha recommendation for one hectare using DAP: Urea needed = 209.83 kg.
Frequently asked questions
What is test weight?
The mass of 1000 seeds in grams; it varies with variety, so use the seed lot’s own value.
Why correct for germination and purity?
Only pure, live seed produces plants: dividing by germination × purity gives the seed to sow.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures .
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Seed Rate Calculator. Retrieved October 29, 2026, from https://scientificconverters.com/calculators/seed-rate-calculator/
IEEE
Scientific Converters, "Seed Rate Calculator," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/calculators/seed-rate-calculator/