FREE SOFTWASH MIX CALCULATOR

Stop guessing your
chemical ratios.

Calculate your exact water-to-chemical mix instantly for siding, roofs, and concrete. Built for solo exterior cleaners.

Mix Ratio = 1 : 7.5

Tired of doing this manually for every quote? WashBase automatically calculates your chemical mixes, estimates surface area, tracks jobs, and sends professional invoices to your clients.

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Common Softwash Mixing Ratios

ApplicationTarget SH StrengthCommon Batch Mix Ratio (using 12.5% SH)
Vinyl Siding / House Wash1.0% - 1.5%1 : 7.3
Concrete / Driveways3.0% - 4.0%1 : 2.1
Roof Cleaning4.0% - 6.0%1 : 1.1

How to Calculate Your Softwash Ratios by Hand

To find your mix ratio, divide your starting chemical strength by your target mix strength, then subtract 1. For example, if you have 12.5% bleach and want a 2% mix: (12.5 / 2) - 1 = 5.25. You need 1 part bleach to 5.25 parts water.