It varies by country and agricultural use type (primarily cattle, mainly grain, etc.)

Where I am, the grain district of Western Australia:

    ALMOST two-thirds of the farming population in the agricultural area of Western Australia live on farms of 1,000 acres or more in size.

and

    The average farm size in WA is approximately 4500 hectares (11,000 acres).

https://library.dpird.wa.gov.au/cgi/viewcontent.cgi?article=...

https://www.agric.wa.gov.au/sites/gateway/files/Grain%20prod...

Both those statements are true, most farms are greater than 1K acres, and the average size of a grain farm is 11,000 acres.

My neighbour shoots ULR targets at 5,000 yards across his property.

Most of the grain growing here is family dynasty type ownership.

Cattle stations get much much bigger.

I wouldn't consider those numbers small, though? That is nearly the size of the city I live in. Not saying you are wrong. Just acknowledging the numbers. This feels like calling Amazon a small business, because it isn't Walmart.

The standard measure would be number of employees, wouldn't it?

50 beef cattle is hobby farm size. It wouldn't provide enough revenue to support a family. We needed grains, oilseeds, pigs and chickens in addition to the 50 beef cattle to support ours.

11,000 acres in Saskatchewan (and presumably Australia) is family farm size. It will have 0 or 1 employees.

Why is that the standard measure? By that rubric, an overwhelming number of small businesses can't support families. Certainly without a lot of supplemental income.

I'm ok with the definition that most farms just aren't small. Certainly ok with the idea that a small farm is still giant compared to any other "small" business. But I find it odd that Clarkson's Farm, a show many are probably familiar with today, is literally 1/10 the size of what you are calling a small farm. Is that just a tiny farm?

Edit: Finally tried clicking around your links, I think you messed up the WA one. At any rate, I see a "small" farm is designated by revenue of about 28k. https://cms.agr.wa.gov/WSDAKentico/Imported/641-WSDAAgInfogr..... shows that "63% of farms are less than 50 acres" So, I can see how your average number can work, as that is how statistics work. That said, most farms are clearly not 11k acres.

Edit2: Annoyingly, that link I put up indicates the "small" revenue is 250k. It was an exemption of some sort that I closed the link on that indicated 28.

Because size is irrelevant. A 1 acre greenhouse can produce more calories and imcome than a 10,000 acre dryland farm.

And all real farms have at least 6 figures of revenue. They also have at least 6 figures of expenses. A small combine harvester costs $500,000, for example.

If you are using 500k equipment, you are no longer a small farm, though? You are small for large farms, maybe. But not what anyone would think of as a small farm.

I'm curious what the exemptions are on runoff regulations. That was the driver for what got me asking.