Sanitizer Concentration Calculator

Concentrate Needed applies the standard dilution formula C1 x V1 = C2 x V2 — solved for the volume of concentrated sanitizer needed to reach Target PPM in Water Volume, given how concentrated your stock solution is (Concentrate Strength). Water Volume is a direct linear multiplier, while Concentrate Needed is inversely proportional to Concentrate Strength — a stronger stock solution needs proportionally less of it to hit the same target. Both relationships are real and can move the result substantially; which one swings Concentrate Needed further depends on where you're starting from within each input's declared range, so neither reliably dominates the other across every scenario. The reference ranges differ in how directly the Food Code supports them. Iodine's 12.5 to 25 ppm is the literal range in Food Code 4-501.114(B). Chlorine's upper bound of 200 ppm is the federal no-rinse food-contact tolerance in 40 CFR 180.940, and 50 ppm is the Food Code's working minimum at 100F and pH 10 or below.

For quaternary ammonium the Food Code gives no number at all — it defers entirely to the EPA-registered product label — so the range shown is the common labelled working band capped at the same 200 ppm no-rinse tolerance; a product labelled for a higher concentration needs a potable-water rinse afterward. Chlorine's 7-second minimum contact time applies only at a 50 mg/L solution with pH 10 or below and water at 100F or warmer (or pH 8 or below at 75F) — otherwise chlorine needs 10 seconds, and quat and iodine both fall under the Food Code's 30-second "other chemical sanitizers" rule regardless of concentration. These are general reference ranges, not a substitute for the specific product label instructions on your sanitizer, which take precedence — some manufacturer-formulated products are approved at concentrations outside these general ranges. Estimated Cost deliberately ignores Concentrate Strength: it prices the sanitizing power delivered (Water Volume x Target PPM) rather than the volume of stock consumed, so a stronger concentrate shows the same cost for the same target even though you use less of it. It is a rough per-gallon cost heuristic for budgeting only, not a verified pricing figure.