Making liquid hand sanitizer requires just three or four ingredients, and the most reliable recipe comes from the World Health Organization’s formulation guide, designed for situations where commercial products aren’t available. The key requirement: your finished product needs at least 60% alcohol to effectively kill bacteria and viruses. The WHO formulations aim higher, targeting 80% ethanol or 75% isopropyl alcohol, which gives you a comfortable margin of effectiveness.
The Two WHO-Recommended Formulations
Both recipes produce one liter (about 34 ounces) of liquid hand sanitizer. They use different types of alcohol but follow the same basic structure.
Ethanol-Based (Formulation I)
- Ethanol 96%: 833.3 ml
- Hydrogen peroxide 3%: 41.7 ml
- Glycerol 98%: 14.5 ml
- Distilled or boiled-then-cooled water: enough to reach the 1,000 ml mark
Isopropyl Alcohol-Based (Formulation II)
- Isopropyl alcohol 99.8%: 751.5 ml
- Hydrogen peroxide 3%: 41.7 ml
- Glycerol 98%: 14.5 ml
- Distilled or boiled-then-cooled water: enough to reach the 1,000 ml mark
Pour the alcohol into a clean graduated container first, then add the hydrogen peroxide, then the glycerol. Top up with water to the one-liter line and shake gently to combine. That’s it. The result is a thin liquid, not a gel, which is why it works well in spray bottles or pump dispensers.
What Each Ingredient Does
The alcohol is the active germ-killing agent. It destroys bacteria and viruses by breaking down their outer protective structures on contact. Both ethanol and isopropyl alcohol work well for this purpose. The CDC recommends a minimum of 60% alcohol concentration for hand sanitizer to be effective, and these WHO formulations exceed that threshold.
Hydrogen peroxide is not in the formula to disinfect your hands. It’s there to kill bacterial spores that may be lurking in the raw ingredients or your mixing container. Alcohol alone doesn’t reliably destroy spores, which are dormant, tough-shelled forms of certain bacteria that can survive in bulk solutions and additives. The small amount of hydrogen peroxide at 3% concentration handles that contamination risk during production. Once the sanitizer is mixed, the hydrogen peroxide is too diluted (0.125% in the final product) to do much on your skin.
Glycerol acts as a moisturizer. Frequent alcohol use dries out skin, and glycerol helps protect the skin barrier and improve how the product feels. There’s a tradeoff here: research has shown that glycerol slightly reduces the antibacterial performance of alcohol-based rubs, particularly over longer periods. But the skin protection it provides makes people more willing to use sanitizer regularly, which matters more in practice. Keep the glycerol at the recommended 1.45% and you get the moisture benefit without meaningfully reducing germ-killing power.
Choosing Your Alcohol
If you’re buying ingredients, your choice between ethanol and isopropyl alcohol often comes down to availability and cost. A few things to keep in mind:
Ethanol must be at least 96% purity (sometimes labeled as 190-proof). Do not use denatured alcohol products that contain methanol, which is toxic and can be absorbed through skin. Check the label carefully. Isopropyl alcohol should be 99% or higher purity for this recipe. The common 70% rubbing alcohol sold in drugstores is too diluted to use in these formulations, since adding the other ingredients would push your final alcohol concentration below the effective range.
Both types of alcohol are effective against most common bacteria and viruses. Neither one has a significant advantage over the other for everyday hand hygiene, so use whichever you can source at the right concentration.
Mixing Equipment and Containers
Use a clean glass or food-grade plastic container with volume markings so you can measure accurately. A graduated flask or a large measuring pitcher works well. Wash and dry your container before starting. If you don’t have distilled water, boil tap water and let it cool completely before using it. This reduces the chance of introducing contaminants into your batch.
For storage, glass bottles or HDPE plastic bottles (the type used for most household cleaning products) are both suitable. If you plan to carry the sanitizer, small spray bottles or pump bottles make dispensing easier. Label every container clearly so no one mistakes it for water or another liquid.
Let the mixed batch sit for 72 hours before use. This waiting period gives the hydrogen peroxide time to destroy any spores that might have been present in the ingredients or container.
Fire Safety During Mixing and Storage
Both ethanol and isopropyl alcohol are highly flammable. Pure isopropyl alcohol has a flash point of just 53°F (12°C), meaning it can ignite at room temperature if exposed to a spark or flame. This is the single biggest safety concern when making hand sanitizer at home.
Mix in a well-ventilated area, ideally outdoors or near an open window. Keep all alcohol containers and your mixing setup far from stoves, candles, pilot lights, space heaters, and anything that produces sparks. Don’t smoke anywhere near your work area. Store finished sanitizer away from heat sources and out of direct sunlight.
After applying hand sanitizer, rub your hands until they feel completely dry before going near any heat source, open flame, or situation involving sparks or static electricity. The alcohol vapors on wet hands are what catch fire, so full evaporation is your safety margin.
Scaling the Recipe
The WHO formulation is designed around a one-liter batch, but you can scale it up or down by keeping the ratios the same. For a smaller 500 ml batch using the ethanol formula, you’d use about 417 ml of ethanol, 21 ml of hydrogen peroxide, 7.25 ml of glycerol, and water to fill to 500 ml. For a 250 ml batch, halve those numbers again.
Precision matters more with the hydrogen peroxide and glycerol than with the water. A little extra water won’t ruin the batch, but significantly more glycerol could make the product feel sticky and reduce its effectiveness. Use a syringe or small measuring cup for the smaller volumes if you don’t have a graduated cylinder.
Limitations of Homemade Sanitizer
This liquid formula won’t feel like the thick gel you buy at the store. Commercial gels contain thickening agents that keep the product on your hands longer, and those additives require more precise chemistry to incorporate without disrupting the alcohol concentration. The liquid version works just as well against germs, but it runs off hands faster, so you need to rub briskly until your hands are dry.
Hand sanitizer of any kind is less effective when your hands are visibly dirty or greasy. In those situations, soap and water is the better choice. Sanitizer also doesn’t work well against certain types of contamination, including some chemicals and heavy soiling from gardening or cooking.
Keep your homemade sanitizer away from children and pets. The high alcohol content makes it dangerous if swallowed. If someone accidentally ingests it, contact the Poison Help Line at 1-800-222-1222.