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Rate Calculator

Calculate the dosage rate based on your land or applicator size, and the dosage rates outlined in each instruction booklet.

Most Apparent products will include an application rate of ml, L, g, kg per hectare (Ha) or per 100L within the Instruction Booklet, based on the type of weed, pest  (or other situation) and will include comments on application.

Use the calculators and examples below to determine how much of any Apparent product to use, based on the amount/rate specified in an Instruction Booklet.

  • Important information

    • Always carefully read the label/booklet/permit before use.
    • The label is a legal document and off label/permit use is not permitted.
    • Before opening, carefully read Directions for Use, Precautionary Statements, Safety Directions, First Aid Instructions and Conditions of Sale (see below).

    The highest risk for a user is not using a pesticide, or any chemical, as directed on the label (or permit).

  • How to calculate the volume of water (spray rate)

    Spray rates can vary based on the manufacturer’s registered label , it’s crucial you know how much water is required to cover the area you are spraying.

    If you are using a spot sprayer like a knapsack or ATV sprayer, you will need to know in advance how much water you will need to cover the area.

    There are a few ways to calibrate this yourself, including:

    • Conducting a small trial using just plain water (no chemical) via your knapsack or handgun. Spray a given area, for example, 25 x 20 metres, and see how much water you used, OR
    • Spray a given amount of water (for example 5 litres), and see how much area it covered.

    Once you have a defined amount of water required, you can enter the amount in the Volume Calculator below.

    If you’re using a spot sprayer and you need to calculate an amount per hectare (per/Ha), you will also need to measure the area you are going to cover, usually in sq/m, or hectares. (1 Ha = 10,000 sq metres)

  • How to calculate how much Apparent product to use

    Each Instruction Booklet will either have the application rates as:

    • Rate per hectare (rate/Ha); or
    • Rate per 100L* (rate/100L)

    * In some instances the rate may be less than rate/100L, for example rate/5L.

    In order to calculate the amount of chemical to use for a given situation, you will need to know:

    • The volume of water required (spray rate) to cover the area or situation (see above);
    • The area of land you are going to cover.

    Once you know the water volume, follow these steps to find the right solution for your situation.

    1. Once you have selected a product, open (or download) the Instruction Booklet and find the situation that matches your situation
    2. Take note of the rate/Ha or per rate/100L in the Instruction Booklet
      • If rate/Ha – Calculate Dosage by Area (below)
      • If rate/100L – Calculate Dosage by Water Volume Size (below)
    3. Enter the values as defined in each calculator and press calculate
    4. Take note of the amount of chemical required to apply

    If the rate is rate/Ha

    1. Calculate the area you are going to cover in sq/m, or hectares
    2. Calculate the volume of water (spray rate) required to cover the area in Litres
    3. The following steps can be done using the Dosage by Area Calculator (below)
      • Convert the area you are going to cover into hectares
      • Multiply the rate (per/Ha) by the converted area
      • You will now have the volume (in L or Kg) needed for that area
    4. Add the calculated chemical amount to the volume of water (spray rate)
    5. Multiple the calculated chemical amount by the tank size/volume of water (spray rate) to the full amount required to fill tank

    If the rate is rate/100L

    1. Calculate the volume of water (spray rate) required to cover the area in Litres
    2. The following steps can be done using the Dosage by Volume Calculator (below)
      • Multiply the application rate (from Booklet) by the spray rate and divide by 100L
      • You will now have the exact amount required for the area based on the spray rate

    Note: You can also enter the size of the tank (instead of the spray rate) to get the amount to put into a full tank.



See the following examples of rate calculation

  • Calculation example: Small area using a 15L knapsack

    You have an area of 25m x 20m you need to cover using a knapsack. You are looking to control Kikuyu in a garden of shrubs in your garden using Salvo 212. You live in Queensland.

    To calculate the application amount rate required you will need to:

    • Take note of the RATE/Ha in the Apparent instruction booklet and any critical comments that relate to application of each product
      The rate of application is 2L or 4L per/Ha
    • Measure the area in which you intend to cover (in m/sq, acres, km/sq or hectares)
      Example: 25m x 20m is equal to 500sq/m
    • Calculate the application rate of the knapsack – See above
      Example: It take  5L of water required to cover 500 sq/m

    Use the Calculate Dosage by Area tool below or calculate manually using these steps:

    • Convert 500sq/m to hectares
      Use the land area converter below – 500sq/m = 0.05 hectares
    • Multiply the per converted area (per hectare) by the dosage rate
      Multiply 0.05 hectares by 2L or 4L = 0.1L or 0.2L for 500sq/m
    • Multiply the amount required by the spray rate
      0.1L or 0.2L required for 5L of water
    • Calculate the amount required per tank
      For a 15L tank, you will need to add (15L/5L) per tank –
      That’s 0.3L or 0.6L required for a 15L tank of water
  • Calculation example: Pasture using a boom spray

    You have an area of 50.7 acres of pasture land and you want to apply a herbicide using a boom spray (1000L). You want to control Silvergrass using Glyphosate 450 and you are in northern NSW.

    To calculate the application amount required you will need to:

    • Take note of the RATE/Ha and any critical comments that relate to application of each product
      The rate of application (for a Boom Spray) is 1.6L – 2.4L per/Ha
    • Measure the area in which you intend to cover (in m/sq, acres, km/sq or hectares)
      You have calculated the area as 50.7 acres
    • Calculate the spray rate of the boom spray – See above
      Example: 2450L of water required to cover 50.7 acres

    Use the Calculate Dosage by Area tool below or calculate manually using these steps:

    • Convert 50.7 acres to hectares
      Use the land area converter below – 50.7 acres = 20.51756 hectares
    • Multiply the per converted area (per hectare) by the dosage rate
      Multiply 20.51756 hectares by 1.6L or 2.4L = 32.83L or 49.24L for 50.7 acres
    • Multiply the amount required by the spray rate
      32.83L or 49.24L required for 2450L of water
    • Calculate the amount required per tank
      For a 1000L tank, you will need to add (1000L/2450L) per tank
      In this case, you will need 32.83L (x 0.408) or 49.24L (x 0.408) per tank.
      That’s 13.39L or 20.09L per tank
      You will need 2.45 tanks to cover the area of 50.7 acres
  • Calculation example: Crop using a field sprayer (400L tank)

    You have an area of 2680 sq/m of wheat crop land and you want to apply a herbicide using a field sprayer (400L). You want to control Giant Bramble using Apparent Woody and you are in Western Australia

    To calculate the application amount required you will need to:

    • Take note of the RATE/100L and any critical comments that relate to application of each product
      The rate of application is 500ml per/100L
    • Calculate the spray rate of the field sprayer – See above
      Example: You have calculated the you need 218.5L of water required to cover 2680 sq/m

    Use the Calculate Dosage by Water Volume Size tool below or calculate manually using these steps:


    • Convert application rate to spray rate
      Multiply 0.5L x (218.5L/100L) = 0.5L * 2.185 = 1.0925L required
    • Calculate the amount required per tank
      For a 400L tank, you will need 1.0925L (for 218.5L)
      That’s 1.0925L * (400L/218.5L) per tank
      1.0925L * 1.8306636156 = In this case, you will need 2L for a 400L tank*

    * Note: You can calculate the amount required for a tank faster by dividing the tank size by 100L and multiplying by the dose rate. 400L / 100L * 0.5 = 2L per tank.

Calculate Dosage by Area

Use this if the application rate in the Instruction Booklet is in rate/Ha (usually L per hectare).

Calculate Dosage by Water Volume Size

Use this if the application rate in the Instruction Booklet is in rate/100L*

* Note: In some Apparent Instruction Booklets, the rate calculated by lower the per 100L, in this instance – divide the amount calculated (per 100L) by the litre value. For example – If the rate is per 5L, multiply the amount calculated by 0.05 (5/100).

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