Lab tool · Acid–base
pH Adjustment & Buffer Calculator
Pick a product type, enter your measured pH, and we'll estimate how much acid or base to add — and warn you when the target falls outside the range melanin-rich skin tolerates.
Inputs
Matches the acid mantle. Critical for barrier on melanin-rich skin.
Ideal range: 4.5 – 5.5 (sweet spot 5)
Most common pH-down. Use 10–20% solution for control.
6.405.00
Δ −1.40
0.14 gof Citric Acid (anhyd.)
% of batch (pure)
0.140%
Pure substance
0.140 g
Direction
Acidify
Add in 25% increments, mix 2–3 min, re-measure after each. pH meters drift — calibrate with pH 4 and 7 buffer before each session.
Range map
02468101214
Dose estimates are starting points. Polymers, gums, proteins, niacinamide, and salts all buffer differently. Always measure after each addition rather than calculating once and walking away.