Do you need some help calculating Cation Exchange Capacity or Soil Nitrogen Supply? Check out our range of Agronomic Tools below:

Ammonia Volatilisation calculator

Fillery and Kamashita Ammonia Volatilisation calculator is a calculator that provides a simple and logical process whereby the extent of potential short term ammonia volatilisation loss from urea application can be explored. The output is in terms of a most likely % N volatilised based on a range of important soil, water and application factors, and equations described in Fillery and Khimashias’ 2016 Soil Research Journal paper “Procedure to estimate ammonia loss after N fertiliser application to moist soil”.


This calculator provides a platform to estimate the cation exchange capacity (CEC) of neutral and acid soils where direct measurement of CEC is not available from laboratory results. The CEC is calculated from a combination of soil texture, organic carbon and pH. It can be used in conjunction with LimeMate where a lab test does not include measurement of cations.

BPC Soil N Supply Pool calculator

This N supply calculator is supplied for primarily educational purposes showing the relationship between crop supply pools, uptake and internal transport efficiencies for cereals and canola.
It was designed to be used in conjunction with the Nitrogen section of the Back Paddock Company BSM and ProSoil-Grain training courses. It is a more configurable form of the common N budget, allowing the operator to explore the effect of the relative contribution of varies N pools, changes in uptake efficiencies the N pools and N application tactics.

BP SodiCalc

This calculator provides a platform to estimate the soil amendment requirement where the soil is found to be dispersive and the cumulative cost of dispersion is likely to exceed the cost of the amendment. SodiCalc calculates the amendment rate and cost from soil chemical characteristics and supply costs supplied by the user and makes no assumptions about the profitability of the soil amelioration strategy. The Cation Converter tab is a simple tool to restate cation concentrations provided as mg/kg as cmol(+)/kg required by Sodicalc.

BP Water SAR

This calculator provides a platform to estimate the soil amendment requirement where irrigation water is found to have a sodium adsorption ratio (SAR) sufficient to cause soil physical deterioration.

BP NutriCost

This calculator provides a platform to explore the elemental nutrient value in compound fertilisers based on their proportional contribution to its cost price compared to using straight products. Each nutrient is valued equally from an agronomic perspective. Output also provides an indication of the premium being paid for multi-nutrient products versus the same nutrients purchasing separately.

Crop Rotation Nutrient Audit

This calculator provides a platform to develop a simple nutrient budget from removal in produce and total nutrient input from external sources, over a sequence of 5 crops

KakPlan Manure

Kakplan contains a range of calculators to help answer questions about the use of animal manure as a fertiliser or soil ameliorant. The outputs include calculations such as nutrient addition,  nutrient value versus mainstream mineral fertilisers and potential salinity effect.


LimeMate calculator is in two parts:

Part one is LimeMate which is an aid in the calculation of rates of soil amendment require to increase soil pH based on a combination of measured soil chemical parameters, soil chemistry targets, plant species aluminium tolerance and amendment quality. The amendment rate suggested is the greater of the rate required to reduce the soil aluminium saturation to a point where the production of the target species is unlikely to inhibit, or the rate required to raise the pH from the current level to a nominated target pH.

Part two is Product Comparison and it can aid in calculating the most cost-effective source of amendment when there are multiple sources available. The recommended product is based on an assessment of a combination of product effectiveness characteristics, soil targets and costs.

Rams Rule

Rams “Rule of Thumb” calculator is based on research that relates soil water and nitrate-N content measure at sowing to likely grain protein outcome. It is only valid for grain production regions of southern Queensland and NW NSW and soils sampled to depths greater than 60 cm.

Soil Water Converter

This calculator converts laboratory-measured gravimetric soil moisture % (1050C) to an estimated volumetric soil water equivalent in millimetres (mm) based on sampling depth and user input soil bulk density.

Wheat PTA

Wheat Plant Tissue Interpreter is designed to help with the interpretation of crop nutrition status according to its nutrient content of various plant parts and its phenological growth stage.

Stubble Nutrient Value Calculator

Stubble Nutrient Value Calculator lets you calculate the amount and value of nutrient removed in crop residue if removed from the paddock after the grain is harvested.

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