Herbicide Dose & From a.i. to Product
Doses per hectare
Turn a recommended active-ingredient rate into the formulated product to measure out — per hectare, per acre, the field total, and the grams or millilitres per spray tank.
Set the dose
Next: measure 400 g of product into each 200 L tank, agitate, and spray evenly to cover 500 L over the field.
Always follow the product label and local regulations; a.i. rates and pre-harvest intervals vary by crop and weed.
Herbicide dose — key facts
- Solid product
- a.i.(g/ha) ÷ 1000 ÷ (a.i.% ÷ 100)
- Liquid product
- a.i.(g/ha) ÷ a.i.(g/L)
- Total = rate × area
- in hectares
- Spray volume
- doesn't change total product
- Per tank
- total ÷ number of tankfuls
- 50% WP
- = 500 g a.i. per kg
- 480 EC
- = 480 g a.i. per L
- Privacy
- Runs in your browser; nothing uploaded
Get the rate right, every tank
The most common spraying mistake is confusing the active-ingredient rate on the label with the amount of product to pour in. They're not the same: a 50% powder or a 480 g/L liquid contains only part active ingredient, so you always measure out more product than the a.i. figure. Get the conversion wrong and you either let weeds survive and breed resistance, or over-apply, waste money and risk crop damage and illegal residues.
This tool converts the a.i. rate into the formulated product per hectare, per acre, the field total, and the grams or millilitres per spray tank for both solid and liquid formulations. Mix by the per-tank figure and every part of the field gets the correct dose. Pair it with the Sprayer Calibration, Spray & Tank Mix and Pre-Harvest Interval tools for safe, accurate spraying.
No dosing mistakes
Convert a.i. to product the right way, every time.
Mix per tank
Know the grams or ml to add to each tankful.
Buy the right amount
Field total tells you how much product to get.
Solid or liquid
Handles WP/WG and EC/SL/SC formulations.
Frequently Asked Questions
How do I convert an active-ingredient rate to product?+
Labels and recommendations often give the dose as active ingredient (a.i.) per hectare, but you measure out the formulated product. For a solid, product (kg/ha) = a.i. rate (g/ha) ÷ 1000 ÷ (a.i.% ÷ 100). For a liquid, product (L/ha) = a.i. rate (g/ha) ÷ a.i. content (g/L). This tool does both and scales to your area and tank.
What is the difference between active ingredient and product?+
The active ingredient is the chemical that actually controls the weed; the product is the bottle or bag you buy, which is the a.i. plus carriers and additives. A 50% WP has 500 g of a.i. per kg; a 480 g/L EC has 480 g of a.i. per litre. You always apply more product than a.i. because of those carriers.
What does the per-tank figure tell me?+
It's how much product to add to each sprayer tank so the whole field gets the right rate. The tool divides the total product by the number of tankfuls needed to cover the field at your spray volume, giving grams (solids) or millilitres (liquids) per tank — the number you actually measure at the pump.
What spray volume should I use?+
Spray volume (L/ha) depends on the sprayer, nozzles, speed and target. Knapsacks often use 300–500 L/ha; boom sprayers 100–250 L/ha. The volume doesn't change the total product (that's set by the a.i. rate) — it changes the concentration per tank and how many tanks you need. Calibrate your sprayer to know your real volume.
Does the spray volume change how much herbicide I need?+
No. The total product for the field is fixed by the active-ingredient rate and the area. A higher spray volume just dilutes the same product in more water and means more tankfuls; a lower volume means fewer, more concentrated tanks. Get the total right first, then mix it evenly across however many tanks you use.
What is a solid vs liquid formulation?+
Solids include wettable powders (WP), water-dispersible granules (WG) and soluble granules (SG), rated as % a.i. by weight. Liquids include emulsifiable concentrates (EC), soluble liquids (SL) and suspension concentrates (SC), rated as grams of a.i. per litre. Pick the right mode so the maths matches your label.
How do I avoid under- or over-dosing?+
Use the label a.i. rate, convert it to product with this tool, calibrate your sprayer so you know the real spray volume and swath, and mix per tank rather than by eye. Under-dosing lets weeds survive and breeds resistance; over-dosing wastes money, can damage the crop and may breach residue limits.
Can I use this for any area unit?+
Yes — enter the area in acres, hectares, guntha, bigha or m². The tool converts to hectares internally and gives the product per hectare, per acre, per your chosen unit and the field total, plus the per-tank amount. Always cross-check against the product label.
What about tank mixes and adjuvants?+
This tool sizes a single herbicide. For tank mixes, calculate each product's dose separately and check compatibility before combining. Add adjuvants (surfactants, oils) at the label rate per tank or per 100 L. See the Spray & Tank Mix calculator for multi-product mixing.
Is the result a substitute for the label?+
No — always read and follow the product label and local pesticide regulations. Recommended a.i. rates, approved crops, pre-harvest intervals and safety precautions vary by product and region. Use this tool to plan quantities, then confirm everything against the registered label.