Bleach Dilution
Calculate the exact amount of bleach and water needed to create a disinfecting solution at any target concentration. Free bleach dilution calculator with charts for cleaning, pools, and water treatment.
About This Calculator
The Bleach Dilution Calculator helps you determine the exact amount of bleach and water needed to prepare a disinfecting solution at your desired concentration. Whether you are sanitizing kitchen surfaces, treating pool water, or preparing solutions for emergency water purification, this calculator provides instant results with visual breakdowns.
Bleach (sodium hypochlorite solution) is one of the most widely used disinfectants worldwide. The correct dilution ratio depends on the application: the CDC recommends 1 tablespoon of 5-6% bleach per gallon of water (about 0.2% solution) for food contact surfaces, and 1 cup per 5 gallons (about 0.5% solution) for non-porous surfaces. For pool chlorination, target levels range from 3-6 ppm (0.0003-0.0006%).
The calculator uses the standard dilution formula C₁V₁ = C₂V₂, where C₁ is your bleach's concentration, C₂ is your target concentration, and V₂ is your desired final volume. The result V₁ is the volume of bleach stock solution needed; the remainder is water.
Regional Notes
India (IN): Household bleach typically contains 4-6% sodium hypochlorite. For surface disinfection, prepare a 0.5% solution by mixing 1 part bleach with 9 parts water. For drinking water purification in emergencies, add 2 drops of 5% bleach per liter of clear water and wait 30 minutes.
United States (US): Standard household bleach (Clorox, Great Value) contains 6-7.5% sodium hypochlorite. The CDC recommends specific bleach-to-water ratios for different disinfection needs. For COVID-19 and general disinfection, use 1/3 cup bleach per gallon of water (about 0.5% solution). Never use splash-less or scented bleach for disinfection.
United Kingdom (UK): Bleach is commonly sold at 5% sodium hypochlorite concentration. Milton and similar brands are used for sterilizing baby bottles and food equipment. For household disinfection, dilute 100 mL of 5% bleach in 900 mL of water for a 0.5% solution. Always follow COSHH guidelines when handling chemical disinfectants.
Frequently Asked Questions
How do I dilute bleach for disinfection?
To dilute bleach for disinfection, mix unscented bleach (typically 5-6% concentration) with water in the correct ratio. For food contact surfaces, use 1 tablespoon of bleach per gallon of water (roughly 0.2% solution). For non-food surfaces, use 1 cup of bleach per 5 gallons of water (approximately 0.5% solution). Always add bleach to water, never the other way around, and work in a well-ventilated area.
What is the correct bleach to water ratio for cleaning?
The correct bleach to water ratio depends on the application. For general household disinfection, a 1:9 ratio (1 part bleach to 9 parts water) is recommended, yielding approximately 0.5% sodium hypochlorite solution. For food preparation surfaces, a weaker ratio of 1:64 (about 0.08% solution) is sufficient. For mold remediation and heavy-duty disinfection, a 1:4 ratio may be used.
Can I use bleach to purify drinking water?
Yes, bleach can be used to disinfect drinking water in emergencies according to CDC guidelines. For clear water, add 8 drops (about 0.5 mL) of 5-6% unscented bleach per gallon (3.8 L) of water. For cloudy or very cold water, double the amount. Stir and let stand for 30 minutes. The water should have a slight chlorine taste or smell. Only use unscented bleach with no added thickeners, fragrances, or additives.
What concentration of bleach is typically available in stores?
Most household bleach sold in stores contains 5-6% sodium hypochlorite as the active ingredient. In the US, Clorox and similar brands typically contain 6% or 7.5% concentration. In the UK and Europe, bleach commonly contains 5% sodium hypochlorite. In India, liquid bleach is typically available in 4-6% concentration. Always check the label for the exact concentration before diluting.
How do I calculate bleach dilution for pool chlorination?
For pool disinfection, the target free chlorine level is typically 3-6 ppm (0.0003-0.0006%). To calculate the bleach needed for a pool, use the formula: Bleach volume (mL) = (Target ppm × Pool volume in liters × 0.00105 × 100) / (Bleach concentration %). A typical 10,000 gallon (37,850 L) pool requires about 3-4 cups (700-950 mL) of 5% bleach to raise chlorine by 1 ppm.
Is it safe to mix bleach with other cleaning products?
No, never mix bleach with other cleaning products. Mixing bleach with ammonia produces toxic chloramine gas that can cause severe respiratory damage. Mixing bleach with acidic products like vinegar creates chlorine gas, which is also highly toxic. Mixing bleach with rubbing alcohol produces chloroform and hydrochloric acid. Always use bleach alone and rinse surfaces thoroughly before applying any other cleaning product.
What PPE should I wear when handling bleach?
When handling bleach, wear protective equipment including rubber gloves to protect skin from irritation, safety goggles to protect eyes from splashes, and a face mask if working in an enclosed space. Wear old clothing or a chemical-resistant apron. Ensure the area is well-ventilated by opening windows or using fans. If bleach gets in your eyes, flush with clean water for at least 15 minutes and seek medical attention.
How long does diluted bleach remain effective?
Diluted bleach solutions degrade quickly and should be used within 24 hours of mixing. Sodium hypochlorite decomposes when exposed to light, air, and organic matter. For maximum effectiveness, prepare fresh bleach solution daily and store it in a opaque, sealed container away from direct sunlight. After 24 hours, the disinfecting power significantly diminishes, especially at lower concentrations.