How much neutraliser do I need?

For a medium-length perm on medium-density hair, approximately 60ml of neutraliser is needed. The first application should saturate all rods thoroughly. Some perming systems require two applications of neutraliser — blot the first application, then apply a second round. Always follow the manufacturer instructions for your specific product.

Why is neutralising important?

Neutralising stops the chemical process and reforms the disulphide bonds in their new shape. Skipping or rushing neutralisation can result in weak bonds, frizzy results, and hair that drops quickly. The neutraliser contains an oxidising agent (usually hydrogen peroxide) that hardens the new curl pattern into place.

How long should neutraliser be left on?

For perming, neutraliser is typically left for 5-10 minutes. Most systems require a first application of 5 minutes with rods in, then rods are carefully removed and a second application is left for 5 minutes on loose hair. For relaxer neutralisation, it is usually 5 minutes with a thorough rinse after.

Can I use any neutraliser with any perm lotion?

It is strongly recommended to use the same brand neutraliser as the perm lotion. They are formulated to work together — the neutraliser pH and strength are designed to properly counteract that specific perm lotion. Mixing brands can result in incomplete neutralisation and poor results.

CutCalcs

Neutraliser Calculator — Quantities After Perming or Relaxing

Work out neutraliser quantities needed after perming or relaxing services.

Service Type

Hair Length

Hair Density

Product Cost (per litre)

Optional — cost per 1000ml bottle

How We Calculate This

This calculator estimates the volume of neutraliser needed based on hair length, density and the type of chemical service being neutralised.

The formula

Neutraliser (ml) = Base amount x Density multiplier x Service type factor

Relaxer neutralisation requires ~20% more product than perming
Thick hair needs ~30% more to ensure full saturation
Total neutralising time includes application and processing

Frequently Asked Questions

Related Calculators

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pH Calculator

Understand pH levels of hair products and their effect on the hair cuticle.

Last updated: February 2026

All calculations are estimates. Always perform a strand test before chemical services.