Dilution and concentrate arithmetic
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The arithmetic behind a concentrate, which is where the commercial argument lives.
Three calculations
Converting a ratio to a percentage, working out a dose for a container, and cost per use, which is the number a janitorial buyer actually compares.
Dilution ratio to percentage
A ratio of 1:32 means one part concentrate to 32 parts water, so 1 part in 33 total.
That is 1 divided by 33, or about 3.0 percent.
1:10 is 9.1 percent. 1:64 is 1.5 percent. 1:128 is 0.78 percent.
Be explicit about whether your ratio means parts-to-water or parts-to-total, because both conventions are in use and the difference matters at strong dilutions.
Working out the dose
For a 750 ml trigger bottle at 1:32: 750 divided by 33 = 23 ml of concentrate, topped up with water.
Now design the closure so that is easy: a cap that holds roughly that, or a dosing chamber.
A customer told to add 23 ml will add a splash, so the instruction that works is "one capful", and the cap is what makes it true.
Cost per use
The number to lead with, because it is where the concentrate wins.
A 500 ml concentrate at 1:32 makes 16.5 liters of ready-to-use product, which is 22 trigger bottles.
So a concentrate at five times the price of a ready-to-use bottle is still a quarter of the cost per bottle, and it ships at a twentieth of the weight.
Present it that way to a janitorial buyer, who thinks in cost per use, and to a consumer, who mostly does not but responds to the freight argument.