Tools & Calculators
Skip the guesswork. Calculate the right 2-stroke pre-mix ratio, the right fuel additive dose, and the right coolant dilution for any tank, can or system size — in US or metric units.
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2-Stroke Pre-Mix Calculator
Pre-mix any popular ratio from 16:1 to 100:1, then see exactly what each package costs you per gallon of mixed fuel.
Open calculator →Fuel Additive Dose Calculator
Get the exact ounces of P.i., Quickshot, Diesel All-In-One and friends for any tank size — and the cost per treated tank.
Open calculator →Antifreeze Mix Calculator
50/50, 60/40 or 70/30 dilution math for any cooling-system capacity, plus DOMINATOR Coolant Boost dose.
Open calculator →Save up to 25% on every AMSOIL order
Join the Preferred Customer program — no auto-ship, no minimum, free returns. Pay wholesale on every product mentioned in these tools.