Crop Yield Estimate Calculator
Enter plants per hectare and yield per plant (g) to estimate yield per hectare (kg/ha and t/ha). Useful for pre-harvest yield forecasting and planting planning.
Input Data
Results
At a glance:Crop yield estimation is a simple pre-/post-harvest method that estimates yield per area as plants per hectare × average yield per plant. Yield per area depends on two things: how many plants are in the field (planting density) and how much each plant produces (yield per plant). Multiplying them gives total harvest weight per area, converted to the common kg/ha and t/ha: since yield per plant is in grams, divide by 1000 for kilograms, so yield(kg/ha) = plants/ha × yield per plant(g) ÷ 1000, then ÷ 1000 for t/ha. Plants per hectare come from sowing density (plants/m² × 10000) or row/spacing (10000 ÷ row spacing ÷ plant spacing); average yield per plant comes from field sampling — randomly take several representative plants, weigh only the harvestable part (grain, fruit, tuber) and average, ideally near maturity. This density × per-plant method is intuitive and handy for forecasting total yield, planning harvest labour, storage and transport, or comparing density treatments. But it extrapolates from point sampling, so accuracy depends on how representative and uniform the sampling is; field unevenness, edge effects, later fruit drop and losses cause bias, and formal yield measurement should still use whole-plot or multi-point large-quadrat harvest. This calculator performs the core conversion plants/ha × yield per plant → kg/ha and t/ha.
Formula
Yield per hectare: yield(kg/ha) = plants/ha × yield per plant(g) ÷ 1000.
Convert to tonnes: yield(t/ha) = yield(kg/ha) ÷ 1000.
Plants per hectare (if needed) = density(plants/m²) × 10000.
$$Y_{(kg/ha)} = \frac{D_{(/ha)} \times y_{(g)}}{1000}$$$$Y_{(t/ha)} = \frac{Y_{(kg/ha)}}{1000}$$How to Use
- Enter plants per hectare (from sowing density or row/spacing; this site has a tool for that).
- Enter the field-sampled average yield per plant (g/plant).
- The tool instantly returns yield per hectare (kg/ha and t/ha).
Effect of plants/ha and yield per plant on estimated yield
| Plants/ha | Yield/plant | Estimate (t/ha) |
|---|---|---|
| 40,000 | 150 g | 6.0 |
| 60,000 | 150 g | 9.0 |
| 60,000 | 200 g | 12.0 |
| 80,000 | 150 g | 12.0 |
Estimate is proportional to both plant count and per-plant yield; raising density or per-plant yield increases output, but too-high density depresses per-plant yield.
Case Studies
Estimate from density and per-plant yield
A field has 60,000 plants/ha; sampling gives average 150 g/plant.
Yield = 60,000 × 150 ÷ 1000 = 9,000 kg/ha = 9 t/ha.
Use this to forecast total yield and arrange harvest labour and storage.
Trade-off between density and per-plant yield
Raise density from 60,000 to 80,000 plants/ha, but competition drops per-plant yield from 150 g to 120 g.
New estimate = 80,000 × 120 ÷ 1000 = 9,600 kg/ha = 9.6 t/ha, only a slight gain.
If denser planting drops per-plant yield further (e.g. 100 g), estimate falls to 8 t/ha, showing an optimal density exists.
FAQ
How do I get plants per hectare?
Convert from planting density or row/spacing: if you know plants per m², multiply by 10000 for plants/ha; if you know row and plant spacing, plants/ha = 10000 ÷ (row spacing × plant spacing). You can also count actual plants in a few fixed quadrats (e.g. 1 m²) and extrapolate. This site also has planting-density/spacing and seeding-rate calculators to use together.
How to sample yield per plant accurately?
Randomly sample enough plants at representative spots (avoid field edges and abnormal areas), weigh only the harvestable part (grain/fruit/tuber) and average. More and more uniform sampling points give better representation. Measure near maturity or harvest, and watch moisture content (dry vs fresh weight differ greatly); convert to a standard moisture basis if needed.
Is this estimate accurate?
It is a quick extrapolation; accuracy depends on sampling representativeness and field uniformity. Uneven fields, missing plants, edge effects, pests or later fruit drop and harvest loss all cause bias. It suits pre-harvest planning and treatment comparison; for accurate actual yield, still use whole-plot or multiple large-quadrat harvest weights.
Why doesn't denser planting always raise yield?
Higher density adds plants but intensifies competition for light, water and nutrients, lowering average per-plant yield. Area yield = plant count × per-plant yield, where the two offset each other, so there is usually an 'optimal density' that maximizes yield; beyond it, the per-plant drop outweighs the plant gain and total yield falls. Choose density considering variety, soil fertility and management.
Does moisture content affect the result?
Yes, and greatly. Fresh (wet) weight is far above dry weight, and cereals are often reported at a standard moisture (e.g. paddy 14%). If sampling weighs fresh but reporting/comparison uses dry (or standard moisture) weight, convert first or yield is overestimated. Ensure yield per plant and final reported yield use a consistent moisture basis.
Related Tools
References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.