Chemical Services Calculators
Perm rod sizing, relaxer application, keratin treatments, processing times, neutraliser quantities and hair science tools.
Perm Rod Calculator
Determine perm rod sizes, quantities and winding patterns for different curl results.
Relaxer Calculator
Calculate relaxer quantity and processing time based on hair type and condition.
Keratin Treatment Calculator
Estimate keratin product quantity and processing time for smoothing treatments.
Chemical Processing Calculator
Calculate safe processing times for colour, bleach and chemical services.
Neutraliser Calculator
Work out neutraliser quantities needed after perming or relaxing services.
pH Calculator
Understand pH levels of hair products and their effect on the hair cuticle.
Strand Test Calculator
Plan strand test timing and record results for chemical service safety.
Porosity Calculator
Assess hair porosity level and get product and processing recommendations.
8 free calculators in Chemical Services
Chemical Hair Services — Safety and Precision
Chemical services including perming, relaxing and keratin treatments permanently alter the hair structure. Getting the timing, product quantities and technique right is essential for healthy results and client safety. Always perform a strand test and skin patch test before any chemical service.
Perming solutions work by breaking and reforming the disulphide bonds within the hair cortex. Processing time depends on hair type, porosity and the strength of the lotion. Over-processing leads to damage, while under-processing results in a weak curl that drops quickly. Standard processing times range from 10-20 minutes for most acid and alkaline perms.
Hair porosity — how readily hair absorbs and retains moisture — is the single most important factor in chemical service success. Low-porosity hair has a tight, closed cuticle and resists chemical penetration. High-porosity hair (often from previous chemical damage) absorbs products quickly and requires reduced processing times and gentler formulations.