About this site

One engine behind every number

Each calculator on the site is a small, openly described formula: area from the sides of a field, product from a nutrient rate and a bag analysis, seed from a target population and a germination figure. The same code runs in three places - the calculator you type into, the worked example printed under it, and the direct answer at the top of each page. A figure in the text therefore cannot drift away from what the tool computes, and before anything is published an automated check compares every number in the text with the engine’s own output.

The formulas are also tested against values worked out independently of the code: geometry done by hand, published unit definitions, and checks such as “double every side of a field and the area must grow four times”. A formula that fails those checks does not ship.

What the calculators refuse to do

• Invent a regulated number. Where a figure depends on law or on a public body - a nitrogen ceiling, a tax rate, a statutory income figure - the page names the clause and the date it was checked. Where a figure could not be verified, the calculator leaves it out rather than guess.
• Republish a standards table. A page shows the value your inputs produced and where it comes from, never a whole reference table copied from someone else’s publication.
• Pretend a recommendation is a rule. A university rate range for corn nitrogen is advice; the page says so in those words.
• Keep your data. What you type stays in your browser. The fields you save live there too, and one visible link forgets them.

The job sheet and the share link

Every result can be passed on. The link under a result reopens exactly the same case - inputs and all - so a grower can send a contractor the job instead of a screenshot of it, and the printable job sheet carries this case’s totals for the operator in the yard.

Five editions, five markets

The site is written separately for the United States, Germany, Poland, France and Mexico, not translated from one master copy. Each edition covers the tools its market actually searches for - US growers ask about acreage, corn and grain bins; German and Polish growers ask about seeding rates in kg/ha; in Mexico the question is how many square metres a plot has. The English edition works in acres, pounds and bushels by default.