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CAFRE Online Nutrient Calculators


CAFRE Online Nutrient Calculators

The CAFRE Online Nutrient Calculators provide help with the Nutrients Action Programme (NAP) measures on nutrient limits, storage requirements and record keeping. To access the calculators log onto

There are five Farm Nutrient Calculators which are free, easy to use, available 24 hours per day, secure and confidential. The Farm Nutrient Calculators are designed to help you meet the requirements of the NAP:

  • Nitrogen loading calculator: Helps you to calculate the nitrogen loading for your farm and check if you are below the 170 kg N per ha per year limit or, if operating under a derogation, below the 250 kg N per ha per year limit.
  • Manure storage calculator: Helps you to calculate the weekly slurry, dirty water, manure production and current storage capacity for your farm and check if you have the required 22 or 26 weeks’ storage or how much additional storage is needed.

(Livestock numbers are required for the above two calculators. An accurate record of cattle type and numbers kept each year since 2007 can be obtained using the ‘Nitrate Animal Count’ function on APHIS Online.)

  • Crop nutrient calculator: This programme will help you to comply with nutrient limit requirements and draw up a nutrient management plan (NMP) for your farm:-

–              determine the N, P2O5 and K2O required by crops;

–              calculate the amount of nutrients supplied by organic manures;

–              select the correct chemical fertiliser and application rate; and

–              retain information required for record keeping.

(Although not a requirement of the Regulations, this calculator also provides information in relation to potash requirements. When this calculator is used for all three main nutrients (N, P2O5 and K2O) it will help to improve soil fertility, optimise application rates, increase crop yields and help to reduce chemical fertiliser costs.)

  • Phosphorus balance calculator: If operating under a derogation, helps you calculate the phosphorus balance for your farm and check that the limit of 10 kg P per ha per year has not been exceeded. For all farms it helps you manage phosphorus inputs and outputs to use phosphorus efficiently.
  • N-max for grassland calculator: Helps you to check that nitrogen applications to the whole grassland area on the farm do not exceed the NAP limits