The kit · oxidizer
Hydrogen peroxide 3%: what it removes and where never to use it
The 3% solution sold in brown bottles at pharmacies. A mild oxidising bleach.
- pH
- 4–5
- Safe on
- 0 materials
- Never on
- 2 materials
- Used in
- 58 files
01 How to use it
Use only a peroxide product labelled for the material, at its labelled strength and contact time; pretest and rinse as directed. Keep it in its dark bottle; use its expiry date and storage instructions. Fizzing on an arbitrary surface is not a reliable strength test.
- It can bleach dyes, so test colours first.
- Do not mix with vinegar, chlorine bleach or other cleaning products. The vinegar restriction is not limited to closed containers.
How it works
Oxidisers break the chemical bonds that make many stains coloured, so the stain stops absorbing light even if some residue remains. They work on tannins, dyes and plant pigments, not on grease or mineral particles.
On a label
On an ingredient list, hydrogen peroxide shows up as hydrogen peroxide (also in many "oxy" sprays).
Hydrogen peroxide is ruled out on leather and suede. Avoid routine home use on jeans, a wool sweater, silk, a wool rug, a wood table and a painted wall. The table gives general restrictions; an unlisted restriction is not proof that a product is compatible.
02 What it works on
- Dye
- Tannin
- Protein
- Oil-soluble pigment
- Living mould
- Urine residue (urea, uric acid)
Hydrogen peroxide is strongest against dye and tannin, and useful on protein, oil-soluble pigment and living mould. It is part of the method in 58 stain files, for stains such as red wine, coffee, tea, cola, orange juice and matcha.
03 Where it is safe
| Material | Verdict | Why |
|---|---|---|
| Leather | Never | Peroxide bleaches and dries leather. |
| Suede and nubuck | Never | Peroxide leaves pale blotches on suede. |
| Jeans | Avoid | It bleaches indigo, so denim gets a light patch where the stain was. |
| Wool and cashmere | Avoid | Professional peroxide spotting is not a universal home method for wool or silk. Use a product explicitly approved for the garment or consult a specialist. |
| Silk | Avoid | Professional peroxide spotting is not a universal home method for wool or silk. Use a product explicitly approved for the garment or consult a specialist. |
| Wool rug | Avoid | Professional peroxide spotting is not a universal home method for wool or silk. Use a product explicitly approved for the garment or consult a specialist. |
| Wood furniture and floors | Avoid | It can lighten wood and soften some finishes. |
| Painted walls | Avoid | It can lighten coloured paint. |
| Clothes | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| White shirt | Test first | No material-specific permission is established by this general entry. Check the exact item and product labels and pretest; if compatibility is unknown, consult the manufacturer or a professional. |
| Linen | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Sheets and bedding | Test first | Fine on white cotton; on coloured items it can lighten the dye, so test a hidden spot first. |
| Towels | Test first | Fine on white cotton; on coloured items it can lighten the dye, so test a hidden spot first. |
| Baby clothes | Test first | Fine on white cotton; on coloured items it can lighten the dye, so test a hidden spot first. |
| Polyester | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Leggings and activewear | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Rayon and viscose | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Carpet | Test first | Fine on light synthetic carpet after testing; it can lighten coloured pile. |
| Fabric couch | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Microfiber couch | Test first | Use a light dab and blot; do not saturate padding. |
| Velvet upholstery | Test first | It can lighten dyes; test on an inside seam and keep contact short. |
| Car seats | Test first | Use a light dab and blot; do not saturate padding. |
| Mattress | Test first | Fine on white cotton; on coloured items it can lighten the dye, so test a hidden spot first. |
| White sneakers | Test first | No material-specific permission is established by this general entry. Check the exact item and product labels and pretest; if compatibility is unknown, consult the manufacturer or a professional. |
| Marble | Test first | Used in poultices for organic stains on light stone; it can lighten dark stone. |
| Granite | Test first | Used in poultices for organic stains on light stone; it can lighten dark stone. |
| Quartz countertop | Test first | Briefly, then rinse; quartz makers prefer pH-neutral cleaners. |
| Tile grout | Test first | No material-specific permission is established by this general entry. Check the exact item and product labels and pretest; if compatibility is unknown, consult the manufacturer or a professional. |
| Plastic containers | Test first | No material-specific permission is established by this general entry. Check the exact item and product labels and pretest; if compatibility is unknown, consult the manufacturer or a professional. |
04 How the files use it
Hydrogen peroxide appears in 58 stain files. The steps it is used in most:
- Peroxide poultice (37 files): The peroxide oxidises the colour inside the stone while the paste draws it up as it dries.
- Peroxide for the shadow (12 files): Peroxide oxidises the leftover colour. It is a mild bleach, much gentler than chlorine.
- Dab with peroxide (6 files): Peroxide lifts the last of the colour; the fizz is enzymes in the stain breaking it down.
- Peroxide, then dry (2 files): Peroxide lightens the browned fibres; sun would fade the surrounding colour too.
- Peroxide and sun (1 file): Peroxide and UV both lighten the browned cellulose.
05 Mixing
The combinations people ask about most, and what actually happens.
- Can you mix chlorine bleach and hydrogen peroxide? Hazard a burst of oxygen, heat and splashing
- Can you mix white vinegar and hydrogen peroxide? Hazard peracetic (peroxy) acid
- Can you mix baking soda and hydrogen peroxide? Caution a product-dependent combination
- Can you mix hydrogen peroxide and dish soap? Caution a product-dependent combination
- Can you mix hydrogen peroxide and ammonia? Caution a product-dependent combination
- Can you mix hydrogen peroxide and rubbing alcohol? Caution a product-dependent combination
- Can you mix hydrogen peroxide and oxygen bleach? Caution a product-dependent combination
- Can you mix hydrogen peroxide and acetone? Hazard unstable organic peroxides
- Can you mix hydrogen peroxide and lemon juice? Caution a product-dependent combination
06 Files that use it
- Red wine on marble
- Coffee on marble
- Tea on marble
- Cola and soda on marble
- Orange juice on marble
- Matcha on marble
- Grape and cranberry juice on marble
- Tomato sauce and ketchup on marble
- Turmeric and curry on marble
- Mustard on marble
- Chocolate on marble
- Berries on marble
- Beetroot on marble
- Soy sauce on marble
- BBQ sauce on marble
- Avocado on marble
- Hair dye on marble
- Blood on clothes
- Candle wax on marble
- Bird droppings on marble
- Scorch marks on clothes
07 Myth files
- Does hydrogen peroxide remove blood? Yes, especially on whites. It foams because blood's own catalase breaks it down. Test colours first.
08 Questions
What stains does hydrogen peroxide remove?
It works best on dye, tannin, protein, oil-soluble pigment and living mould, which is why it appears in the files for red wine, coffee, tea, cola and orange juice.
How do you use hydrogen peroxide safely?
Use only a peroxide product labelled for the material, at its labelled strength and contact time; pretest and rinse as directed. Keep it in its dark bottle; use its expiry date and storage instructions. Fizzing on an arbitrary surface is not a reliable strength test. It can bleach dyes, so test colours first.
What should you never mix with hydrogen peroxide?
chlorine bleach, white vinegar and acetone. Hypochlorite and peroxide-based bleaches react with each other, releasing oxygen quickly and generating heat. Do not combine commercial cleaners unless their exact manufacturers explicitly permit the use.
Where should you never use hydrogen peroxide?
On leather and suede. Peroxide bleaches and dries leather.