NPK 20-10-10 Explained: Nutrients per Tonne and Crop Uses (2026)

NPK 20-10-10 is a fertiliser grade that contains 20% nitrogen (N), 10% phosphate (P2O5) and 10% potash (K2O) by weight. In other words, every tonne of product carries 200 kg of N, 100 kg of P2O5 and 100 kg of K2O. This guide shows how to read that grade, calculate the nutrient in each tonne and each hectare, and compare it with options such as NPK 15-15-15. It also covers which crops suit a nitrogen-led 2:1:1 ratio and how the grade can be made. Rates and examples are illustrative: your soil test, crop, climate and local rules decide what you should actually apply.

Key takeaways

• NPK 20-10-10 supplies 200 kg N, 100 kg P2O5 and 100 kg K2O per metric tonne, a total of 400 kg of declared nutrient (40% of the weight).
• The ratio is 2:1:1, so it is nitrogen-led. It suits crops that take up much more N than P or K, but it is not a universal grade.
• Phosphorus and potassium are declared as oxides. Elemental P is about 43.6% of P2O5 and elemental K is about 83% of K2O.
• At 300 kg/ha, NPK 20-10-10 supplies 60 kg N, 30 kg P2O5 and 30 kg K2O per hectare. Most crops then need an extra nitrogen top-up.
• A soil test should set the grade. If soil phosphorus or potassium is already high, a 2:1:1 product may waste those nutrients.

What NPK 20-10-10 means: reading the fertiliser grade

A fertiliser grade is the standard shorthand printed on bags and on bulk documents. It tells you the guaranteed percentage of the three primary nutrients: nitrogen, phosphorus and potassium. Once you can read it, you can compare any two products on a like-for-like basis.

The three numbers and what they measure

The numbers always appear in the order N-P-K. In 20-10-10, the first number is total nitrogen (N), the second is phosphate expressed as P2O5, and the third is potash expressed as K2O. A 1,000 kg lot of this product therefore holds 200 kg, 100 kg and 100 kg of those nutrients. The remaining 600 kg is carrier material, such as the ammonium, sulphate or chloride that accompanies each nutrient, plus fillers or conditioners. Some grades also declare secondary nutrients, for example sulphur, after the K figure.

The 2:1:1 NPK ratio meaning

The NPK ratio meaning is simply the grade divided by its smallest number. Dividing 20, 10 and 10 by 10 gives 2:1:1. Two kilograms of N are supplied for every kilogram of P2O5 and every kilogram of K2O. Ratio matters because crops remove nutrients in different proportions. Cereals and leafy crops draw heavily on nitrogen, while fruiting and root crops often take up proportionally more potassium. Two grades with the same ratio, such as 10-5-5 and 20-10-10, differ only in concentration: the second delivers twice the nutrient per tonne.

Oxide versus elemental labelling

Most countries declare P as P2O5 and K as K2O, but this is a convention and not a universal rule. Some regions and some product types declare elemental P and K, or list both. Always check the label or Certificate of Analysis to see which basis is used before comparing grades from different suppliers or countries. The grade on a quote should state clearly what is being declared.

Nutrient per tonne: the calculation for NPK 20-10-10

The core calculation is one line: nutrient (kg) = product weight (kg) × grade percentage ÷ 100. It works for any grade, which makes it the most useful formula for bulk buyers.

Kilograms of nutrient in one tonne

For one metric tonne (1,000 kg) of NPK 20-10-10:

• Nitrogen: 1,000 × 20 ÷ 100 = 200 kg N
• Phosphate: 1,000 × 10 ÷ 100 = 100 kg P2O5
• Potash: 1,000 × 10 ÷ 100 = 100 kg K2O

The declared nutrient total is 400 kg, so the product is 40% active nutrient by weight. A full 20 ft container of about 25 MT would carry roughly 5,000 kg N, 2,500 kg P2O5 and 2,500 kg K2O.

Converting P2O5 and K2O to elemental P and K

Soil tests and some research papers report elemental phosphorus and potassium, so you may need to convert. Multiply P2O5 by 0.436 to get P, and K2O by 0.830 to get K. In one tonne of NPK 20-10-10, 100 kg P2O5 equals about 43.6 kg P, and 100 kg K2O equals about 83 kg K. To go the other way, multiply P by 2.29 and K by 1.20.

Pounds per short ton and per acre

One metric tonne is about 2,205 lb. That means 200 kg N is about 441 lb N, and 100 kg of P2O5 or K2O is about 220 lb. If you work in US short tons (2,000 lb), a short ton of 20-10-10 contains 400 lb N, 200 lb P2O5 and 200 lb K2O. To convert rates, 1 kg/ha equals about 0.892 lb/acre.

Per 1 metric tonne of NPK 20-10-10	kg	lb (approx.)
Nitrogen (N)	200	441
Phosphate (P2O5)	100	220
Elemental phosphorus (P)	43.6	96
Potash (K2O)	100	220
Elemental potassium (K)	83.0	183
Carrier and other material	600	1,323

From tonnes to hectares: application rate maths

Buying by the tonne is one decision; applying by the hectare is another. The link between them is the product rate in kg/ha.

Working out nutrient per hectare

Nutrient per hectare = product rate (kg/ha) × grade ÷ 100. The table below applies this to NPK 20-10-10 at four common rates.

Product rate (kg/ha)	Rate (lb/acre)	N (kg/ha)	P2O5 (kg/ha)	K2O (kg/ha)	Hectares covered per tonne
200	178	40	20	20	5.0
300	268	60	30	30	3.3
400	357	80	40	40	2.5
500	446	100	50	50	2.0

Hectares per tonne is 1,000 ÷ rate. To plan a 250-hectare programme at 300 kg/ha you need 250 × 300 = 75,000 kg, or 75 MT. That is useful when you are matching a farm programme to commercial order quantities.

Topping up the nitrogen gap

Because the grade carries twice as much N as P2O5 or K2O, you can fill the P and K requirement and still fall short on N. Suppose a crop needs 150 kg N/ha and the soil test calls for 40 kg P2O5 and 40 kg K2O. A rate of 400 kg/ha of NPK 20-10-10 supplies exactly 80-40-40. The remaining 70 kg N can come from urea (46% N): 70 ÷ 0.46 ≈ 152 kg/ha of urea. Timing matters, since surface-applied urea can lose nitrogen to the air; our guide to urea volatilisation loss explains how to reduce that waste.

NPK 20-10-10 versus NPK 15-15-15

NPK 15-15-15 is one of the most widely traded balanced grades, so it is the natural comparison. The two products have different jobs, and neither is better in every situation.

Side-by-side nutrient comparison

Per metric tonne	NPK 20-10-10	NPK 15-15-15
Ratio	2:1:1	1:1:1
Nitrogen (kg N)	200	150
Phosphate (kg P2O5)	100	150
Potash (kg K2O)	100	150
Total declared nutrient	400 kg (40%)	450 kg (45%)

NPK 15-15-15 carries more total nutrient per tonne, but its nitrogen is lower. To deliver 60 kg N/ha you need 300 kg/ha of 20-10-10 or 400 kg/ha of 15-15-15. The second option also applies 60 kg each of P2O5 and K2O, twice as much as the first.

When a balanced grade makes more sense

A 1:1:1 grade suits situations where soil tests show all three nutrients are needed in similar amounts, for example establishing perennial crops or building fertility on low-testing ground. A 2:1:1 grade suits fields where P and K are adequate or maintained separately, and nitrogen drives yield. Comparing cost per kilogram of nutrient, not per tonne of product, is the fair test: divide the quoted cost per tonne by the kilograms of the nutrient you need. Our guide on how to compare bulk NPK quotes walks through that method.

Crop examples: where a 2:1:1 grade fits

These examples show the thinking, not fixed recommendations. Target nutrient rates vary widely by yield goal, soil, rainfall and country, so confirm them locally with an agronomist.

Maize and other high-nitrogen cereals

Maize responds strongly to nitrogen, and early growth benefits from some phosphorus near the seed row or band. A pre-plant or at-planting application of NPK 20-10-10 at 300 to 400 kg/ha provides 60 to 80 kg N alongside modest P and K. Later side-dressings of nitrogen, split to match uptake, then cover the rest. On soils already rich in P and K, the extra phosphate in the product is a cost with little return.

Leafy vegetables and grass crops

Leafy vegetables, sweet corn, turf and grass-based hay or pasture remove a lot of nitrogen, and grasses also remove considerable potassium. A 2:1:1 grade fits where soil P is adequate and nitrogen is the main driver. For hay and pasture, our page on fertiliser for pasture and hay gives Australian context on nutrient removal and rate planning.

Wheat and canola: check phosphorus and sulphur

Cereals such as wheat often receive phosphorus at sowing, and many programmes rely on DAP or MAP for that. A 20-10-10 grade can supply too much N at sowing relative to P in some systems, so check the phosphorus requirement first. Canola has a high sulphur demand, and a standard 20-10-10 carries no sulphur unless it is declared. If sulphur matters for your crop, ask for it to be included in the specification.

How a 20-10-10 grade is made: compound or blend

The same grade can reach you in two different physical forms, and the choice affects handling, uniformity and flexibility.

A worked blend recipe per tonne

A blender can reach 20-10-10 by combining single-nutrient or two-nutrient materials. The arithmetic below uses typical analyses: urea 46-0-0, DAP 18-46-0 and muriate of potash (MOP) 0-0-60, with sulphate of potash (SOP, 0-0-50) as a chloride-free alternative. Actual product analyses vary, so recipes are always confirmed against the real material.

1. Phosphate: 100 kg P2O5 ÷ 0.46 = about 217 kg DAP, which also supplies about 39 kg N.
2. Potash: 100 kg K2O ÷ 0.60 = about 167 kg MOP, or ÷ 0.50 = 200 kg SOP.
3. Remaining nitrogen: 200 − 39 = 161 kg N ÷ 0.46 = about 350 kg urea.
4. Total active materials: 217 + 350 + 167 = about 734 kg with MOP (767 kg with SOP). The remaining 233 to 266 kg is filler or other nutrients, such as sulphur or trace elements, as specified.

Chloride-sensitive crops, such as some fruit, tobacco and vegetables, are the usual reason to choose SOP over MOP.

Compound granules versus a bulk blend

In a compound fertiliser, every granule contains all three nutrients, which gives uniform distribution and resists separation in handling. A blend mixes separate granules, which allows an exact match to a soil test but needs similar granule size to avoid segregation. Our comparison of fertiliser blend versus compound fertiliser sets out the trade-offs in detail. We supply both compound NPK, including high tower compound, and blended fertiliser.

Is NPK 20-10-10 right for your soil? Buying in bulk

A grade only makes sense in the context of what the soil already holds. Choosing 20-10-10 because it is familiar is a common and avoidable mistake.

Let the soil test decide the grade

Compare soil test values with the crop’s critical or target levels. If phosphorus and potassium test low, the grade may need more of both than 2:1:1 provides. If they test high, a nitrogen-only source or a lower-P grade can be cheaper per useful kilogram. Our walkthrough on how to read a soil test report shows how those values lead to a blend decision. Local regulations on nutrient application, especially phosphorus and nitrogen limits near waterways, differ between countries and regions, so check what applies where you farm.

Ordering from Natures Fertilizer

Natures Fertilizer Pty Ltd blends in Hamilton, South Australia, and supplies growers, resellers and agronomy businesses in commercial quantities. Minimum orders are 10 to 25 MT depending on product and destination, and a full 20 ft container is about 25 MT. This website is a catalogue and enquiry point, not a shop. Every enquiry receives an individual written quote that confirms the specification and lead time. We match blends to your soil test, and a Certificate of Analysis is available on request. Payment is by bank transfer: EFT within Australia and T/T for export. For a worked example of the process, see our guide to custom fertiliser blending from soil test to order.

Conclusion

NPK 20-10-10 is a 2:1:1 grade that delivers 200 kg N, 100 kg P2O5 and 100 kg K2O in every metric tonne. Multiplying the product rate by the grade gives the nutrient per hectare, and any nitrogen shortfall can be closed with a separate source such as urea. Compared with NPK 15-15-15, it puts more weight on nitrogen and less on phosphorus and potassium. Whether it is the right choice depends on the crop, the soil test and local rules, and the grade can be supplied as a compound or a blend.

Frequently asked questions

What does NPK 20-10-10 mean?

It means the fertiliser contains 20% nitrogen (N), 10% phosphate (P2O5) and 10% potash (K2O) by weight. Per metric tonne, that is 200 kg N, 100 kg P2O5 and 100 kg K2O. The ratio is 2:1:1.

How much nitrogen is in a tonne of NPK 20-10-10?

One metric tonne (1,000 kg) contains 200 kg of nitrogen, which is about 441 lb. A US short ton (2,000 lb) contains 400 lb of nitrogen.

How much NPK 20-10-10 do I need per hectare?

There is no single rate, because it depends on the crop, yield goal and soil test. As a guide to the maths, 300 kg/ha supplies 60 kg N, 30 kg P2O5 and 30 kg K2O per hectare. Always set the rate from a soil test and local agronomic advice.

Is NPK 20-10-10 better than NPK 15-15-15?

Neither is better in every case. NPK 20-10-10 suits crops and soils where nitrogen is the main need, while NPK 15-15-15 suits situations that need all three nutrients in similar amounts. Compare the cost per kilogram of the nutrient you actually need.

Are P2O5 and K2O the same as phosphorus and potassium?

Not exactly. They are oxide forms used for labelling. Elemental phosphorus is about 43.6% of P2O5, and elemental potassium is about 83% of K2O, so 100 kg P2O5 equals about 43.6 kg P.

Can NPK 20-10-10 be made as a custom blend?

Yes. A blender can combine materials such as urea, DAP and potash to reach the grade, and can adjust it, for example by adding sulphur or using sulphate of potash for chloride-sensitive crops. Natures Fertilizer matches blends to a customer’s soil test.

Does NPK 20-10-10 contain sulphur?

Not as part of the grade name. Sulphur is a secondary nutrient and only appears if the product declares it. Crops with high sulphur demand, such as canola, may need it specified in the order.

What is the minimum order for bulk NPK from Natures Fertilizer?

Minimum orders are 10 to 25 MT depending on product and destination, and a full 20 ft container is about 25 MT. Each enquiry receives an individual written quote that confirms specifications and lead time.