Pool Chemical Cost & Margin Calculator

The hard step incumbents skip is turning a bulk buy into a per-visit cost. Each chemical line divides the container price by how many units are in it to get a cost per unit, multiplies by how much you use per visit, and the lines sum to your chemical cost per visit. Subtract that from your flat rate (on a per-visit basis) and you have the dollar and percent margin remaining.

per chemical line:
  unit cost     = container price / container size
  cost / visit  = unit cost × used per visit
chemical cost / visit = Σ each line's cost / visit

service / visit = (per-month rate) ? rate / visits-per-month : rate
margin $        = service / visit − chemical cost / visit
margin %        = (service − chemical cost) / service       (decimal)
chemical share  = chemical cost / visit ÷ service / visit
monthly margin  = margin $ × visits per month   (on a monthly basis)

Worked example: a $22 bucket of 50 tablets is $22 ÷ 50 = $0.44/tablet; at 6 tablets/visit that's $2.64. Add liquid chlorine ($4 ÷ 1 gal × 0.25 = $1.00) and muriatic acid ($5 ÷ 1 gal × 0.10 = $0.50) for $4.14/visit. On an $18 flat rate the margin is $18 − $4.14 = $13.86 (77.0%), and chemicals are 23.0% of the rate — Healthy.

The Healthy / Thin / Losing-money flag compares your chemical margin against a target you set (60–70% is the typical healthy band): at or above target is Healthy, between break-even and target is Thin, and a negative margin is Losing money. This is chemical margin only — no labor, overhead, drive, or vehicle.