H2o2 Dilution Calculator

Using high-concentration hydrogen peroxide (H2O2) requires precision. Whether you are using 35% food-grade peroxide or 12% solutions, diluting it down to common concentrations like 3% or 6% is essential for safety and effectiveness. This calculator uses the standard dilution formula (C1 × V1 = C2 × V2) to help you determine exactly how much concentrate and how much distilled water you need for your project.

Dilution Tool

The strength of the H2O2 you currently have.

The strength you want to achieve.

The total amount of final solution you want.

Mixing Instructions:

Safety Warning: Always add peroxide to water, not water to peroxide, to prevent splashing of the concentrate.

function calculateDilution() { var c1 = parseFloat(document.getElementById('initialConc').value); var c2 = parseFloat(document.getElementById('targetConc').value); var v2 = parseFloat(document.getElementById('totalVolume').value); var resultArea = document.getElementById('resultArea'); if (isNaN(c1) || isNaN(c2) || isNaN(v2) || c1 <= 0 || c2 <= 0 || v2 = c1) { alert("Target concentration must be lower than the initial concentration."); return; } // Formula: V1 = (C2 * V2) / C1 var v1 = (c2 * v2) / c1; var waterNeeded = v2 – v1; document.getElementById('h2o2Required').innerHTML = "Amount of H2O2 (Concentrate): " + v1.toFixed(2) + " ml"; document.getElementById('waterRequired').innerHTML = "Amount of Distilled Water: " + waterNeeded.toFixed(2) + " ml"; resultArea.style.display = "block"; }

Understanding the H2O2 Dilution Formula

The math behind diluting hydrogen peroxide is based on the conservation of mass. We use the formula:

C1 × V1 = C2 × V2

• C1: Concentration of the starting H2O2 (e.g., 35%).
• V1: Volume of the starting H2O2 you need to measure out.
• C2: Final concentration you want (e.g., 3%).
• V2: Total final volume of the solution.

Common Dilution Examples

Here are some realistic scenarios when diluting 35% Food Grade Hydrogen Peroxide into common household strengths:

Target Strength	Total Desired Volume	35% H2O2 Needed	Water Needed
3% (Standard)	1000 ml	85.7 ml	914.3 ml
6% (Beauty/Hair)	500 ml	85.7 ml	414.3 ml
12% (Cleaning)	1000 ml	342.9 ml	657.1 ml

Safety Precautions for Handling Hydrogen Peroxide

High-concentration H2O2 (anything above 10%) is a strong oxidizing agent and can cause chemical burns to the skin and eyes.

1. Protective Gear: Always wear gloves and safety goggles when handling concentrates.
2. Ventilation: Work in a well-ventilated area to avoid inhaling concentrated vapors.
3. Water Quality: Use distilled water for dilution. Tap water contains minerals that can cause the H2O2 to decompose prematurely.
4. Container Choice: Store your diluted solution in a dark, opaque bottle (like the brown ones used in pharmacies) because light breaks down hydrogen peroxide into water and oxygen.
5. The "Acid to Water" Rule: While H2O2 is not technically a strong acid, the practice of adding the chemical to water (rather than pouring water into a beaker of chemical) is safer as it prevents high-concentration splashing.

Common Applications for Diluted H2O2

• 3% Concentration: Used for general household cleaning, disinfecting surfaces, and minor wound care.
• 6% – 9% Concentration: Often used in hair bleaching and professional dental whitening products.
• 10% – 12% Concentration: Used for heavy-duty mold removal and specialized horticultural applications to oxygenate soil.