ACID RED 33 is graded C (Moderate) by Expert·ING, based on COSING, FDA regulatory data. It is restricted under EU COSING — AnnexIII-SAFETY-.
ACID RED 33
Safety grade: C
Acid Red 33 is a synthetic red colorant commonly used in hair dyes to create vibrant red and pink hair colors. It's a laboratory-made dye that bonds to hair strands to provide long-lasting color.
This ingredient is used in hair dyes to impart red and pink tones to hair by penetrating and bonding to the hair shaft.
Graded using: COSING, FDA.
- EU COSING — Restricted
Last verified: May 26, 2026
Safer alternatives to ACID RED 33
- BASIC RED 76 — Grade A. Basic Red 76 provides red hair color via azo dye chemistry.
Other Hair Dyeing ingredients
- RESORCINOL — Grade E**
- THYMOL — Grade A
- M-AMINOPHENOL — Grade C**
- P-AMINOPHENOL — Grade C**
- 2-METHYLRESORCINOL — Grade C
- 4-AMINO-2-HYDROXYTOLUENE — Grade C
- P-PHENYLENEDIAMINE — Grade D**
- 2-METHYL-5-HYDROXYETHYLAMINOPHENOL — Grade C