Hand Sanitizer Gel
Ingredients
- ⅔ cup isopropyl rubbing alcohol (91% or higher) — MUST be 91% or higher — see explanation below
- ⅓ cup aloe vera gel — pure aloe vera gel, not aloe vera juice
- 10 drops tea tree essential oil — antibacterial — optional but adds protection
- 5–10 drops lavender or peppermint essential oil — optional — for scent and additional antimicrobial properties
- 1 tsp vegetable glycerin — optional — prevents hands from drying out
Overview
Hand sanitizer is straightforward: alcohol kills germs on contact by denaturing their proteins. The CDC says hand sanitizer needs at least 60% alcohol concentration to be effective. The aloe vera gel is there to make it a gel instead of a liquid and to prevent your hands from cracking and drying out from the alcohol.
The critical detail is the math. When you mix ⅔ cup of 91% rubbing alcohol with ⅓ cup of aloe vera gel, the final concentration is roughly 60–62% alcohol — right at the threshold. This is why you must use 91% or higher isopropyl alcohol, not 70%. Starting with 70% alcohol and adding aloe vera would dilute it below the effective 60% threshold, and you’d have a nice-smelling gel that doesn’t actually kill germs.
Washing your hands with soap and water is always better than sanitizer. This is for situations where soap and water aren’t available — car, hiking, travel, shopping.
Instructions
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Combine the rubbing alcohol and aloe vera gel in a clean bowl. Stir (don’t whisk — you don’t want bubbles).
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Add the glycerin if using. Stir to incorporate.
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Add essential oils and stir.
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Transfer to a squeeze bottle or pump bottle using a funnel. Small travel-size bottles work great for carrying in a bag.
How to Use
Apply a dime-sized amount to your palm. Rub hands together, covering all surfaces — fingers, between fingers, backs of hands, fingertips. Rub until hands feel dry (about 20 seconds). Don’t wipe off.
The Alcohol Math
This matters, so here’s the breakdown:
| Starting Alcohol | Mix Ratio | Final Concentration | Effective? |
|---|---|---|---|
| 91% isopropyl | 2:1 (alcohol:aloe) | ~60% | ✅ Yes |
| 99% isopropyl | 2:1 (alcohol:aloe) | ~66% | ✅ Yes |
| 70% isopropyl | 2:1 (alcohol:aloe) | ~47% | ❌ No — below threshold |
Always use 91% or higher. The 70% rubbing alcohol that’s most common in stores is only effective as a sanitizer when used straight — not diluted with anything.
Tips
- Soap and water is always preferable. Hand sanitizer is a backup, not a replacement for hand washing. If you have access to a sink, wash your hands.
- Don’t use homemade sanitizer on wounds or broken skin. The essential oils can irritate open cuts.
- Aloe vera gel, not juice. Make sure you’re buying pure aloe vera gel (thick, clear). Aloe vera juice is too thin and won’t create a gel consistency.
- Flammable. This is 60%+ alcohol. Keep away from flame, sparks, and heat. Don’t leave in a hot car.
- Seal the bottle tightly. Alcohol evaporates readily. If you leave the cap off, the alcohol concentration drops and the sanitizer becomes ineffective.
- Travel bottles: Fill small 2 oz squeeze bottles for bags, car glove box, and hiking packs. Much more practical than carrying the full 8 oz bottle.
- The glycerin is worth including. Frequent alcohol-based sanitizer use dries out skin. Glycerin is a humectant that pulls moisture from the air into your skin — same reason it’s in the personal care recipes in this collection.