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MOSS & SONS · EVERYDAY FARM MATH

A little figuring.
A better plan.

Simple calculators with the steps spelled out. Use the numbers you measured, understand the result, and keep a reminder where it helps.

Miles per gallon

  1. Fill the tank until the pump first shuts off. Do not top it off. Write down the odometer reading.
  2. Drive normally. At the next fill, fill to the same first shutoff point. Record the new odometer and the US gallons just added.
  3. Enter those three numbers. For a steadier average, use several complete fill-ups: total miles divided by total gallons.

A partial fill does not measure a full-tank interval. Dashboard estimates, towing, idling, terrain, and pump shutoff differences can change the result. These units are US gallons, not Imperial gallons.

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Trip fuel budget

  1. Enter the entire trip distance, including the return trip if you will drive back.
  2. Use your measured MPG under similar load and driving conditions.
  3. Enter the fuel price per US gallon. Add a separate allowance for detours and changing prices.

Fuel only. This excludes vehicle wear, insurance, labor, tolls, and delivery charges.

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When will the feed run out?

  1. Weigh the usable feed left. Keep spoiled or contaminated feed out of this number.
  2. Measure how much the whole group actually uses each day, including typical waste. Keep the ration set by your feed plan.
  3. Choose how many days you need to buy or receive more. The result uses today's date on this device.

Inventory arithmetic, not a feeding recommendation. You can also use the same units for bedding or other regularly used supplies. Recheck when animal numbers, growth, weather, or waste change.

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Water in a rectangular tank

  1. Use the inside dimensions of a straight-sided rectangular tank.
  2. Measure length and width in feet. Measure the actual water depth, not the tank's full height.
  3. Convert inches to feet by dividing by 12. Enter the measurements below.

Does not fit round, curved, or tapered troughs. Capacity does not tell you how long animals can go without water; inspect supply and flow every day.

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Posts for a straight fence run

  1. Measure one straight run from end post to end post.
  2. Enter the largest spacing allowed by your chosen fence system.
  3. Repeat for each run, accounting for shared corners separately.

A quantity estimate, not a fence design. Gates, braces, corners, slopes, livestock pressure, utilities, and local requirements need separate planning.

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Paddock rotation arithmetic

  1. Count the paddocks you can actually use, with water and adequate forage.
  2. Choose a tentative number of days in each paddock.
  3. Compare the result with pasture growth and your herd plan. Move sooner if the ground or forage requires it.

Rest days = (paddocks − 1) × grazing days. This does not establish a safe parasite-free interval or stocking rate. Wet weather, grazing height, parasite survival, and forage recovery matter.

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Rectangle to acres

  1. Measure the length and width of a rectangular area in feet.
  2. For an irregular area, divide it into smaller rectangles and add their areas.
  3. Use the result for rough planning, then verify boundaries before buying, fencing, or building.

One acre is 43,560 square feet. This is not a survey or a livestock carrying-capacity recommendation.

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