Detergent Dose Calculator
Calculate the correct detergent dose based on load size, water hardness and soil level.
How We Calculate This
The calculator uses a base dose of 35ml of liquid detergent for a full load in medium-hardness water, then adjusts for load fraction, water hardness and soil level.
Formula
Dose = 35ml × load fraction × hardness multiplier × soil multiplier
Multipliers
- Load fraction: weight ÷ drum capacity (max 1.0)
- Soft water: 0.75x | Medium: 1.0x | Hard: 1.25x | Very hard: 1.5x
- Light soil: 0.7x | Normal: 1.0x | Heavy: 1.4x
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates. Always verify quantities and timings for your specific situation.