Harvest Index Calculator
Calculate harvest index — the ratio of grain (economic yield) to total above-ground biomass.
Harvest index (HI) = economic yield ÷ total biomass. It measures how efficiently a crop turns growth into harvestable product. Modern cereals reach HI 0.4–0.5; a low HI means lots of straw relative to grain, often from excess nitrogen or lodging.
Indicative planning figures based on published research averages. Local soil tests, varieties and weather change actual requirements — confirm with your agronomist or extension officer.
Farmers and agronomists use the free Harvest Index Calculator for an accurate answer in seconds — no formulas to remember, works offline.
About Harvest Index Calculator
Harvest index measures what fraction of a crop's total growth ends up as the part you actually sell — grain, in most cereals. It's a key efficiency and breeding metric: harvest a sample, separate and weigh the grain and the total above-ground biomass, and the ratio is your harvest index. Modern high-yielding cereals achieve 0.4–0.5; a low harvest index signals a crop that grew lots of straw relative to grain, often from excess nitrogen, lodging or stress at grain-fill.
How to use Harvest Index Calculator
- 1Enter your values into the inputs.
- 2Read the headline result and the supporting breakdown.
- 3Apply the guidance in the note to your decision.
Why use Harvest Index Calculator?
- ✓Uses the standard, citable agronomy formula
- ✓Clear inputs with sensible defaults
- ✓Instant result with the working shown
- ✓Free, fully in-browser and private
Frequently asked questions
What is harvest index and how is it calculated?+
Harvest index (HI) is the ratio of economic yield (e.g. grain) to total above-ground biomass: HI = grain ÷ total biomass. An HI of 0.45 means 45% of the crop's dry matter is harvestable grain and 55% is straw and chaff.
What is a good harvest index?+
Modern wheat and rice varieties reach 0.4–0.5; many pulses and oilseeds are lower (0.2–0.35). A low HI for a crop that should be higher often points to excess vegetative growth, lodging or stress during grain filling.
Is this tool free and private?+
Yes — free, no sign-up, and all calculation runs in your browser, so it works offline and your data never leaves the device.
Related Agri tools
Tractor Fuel Consumption Calculator
Estimate your tractor's diesel consumption per hour from its horsepower, load and specific fuel consumption.
● LiveTractor Fuel Cost Per Acre Calculator
Convert your tractor's fuel use per hour into diesel litres and cost per acre for any field operation.
● LiveImplement Field Capacity Calculator
Calculate the effective field capacity (ha/h and acres/h) of any implement from width, speed and field efficiency.
● Live