Propylene Glycol Uses: Soap Making, Lotions & DIY Formulas

Propylene glycol (PG) is one of the most versatile liquids in a DIY formulator's kit. It's clear, nearly odorless and mixes easily with water and alcohol, which makes it useful in everything from soap to room sprays. Here's what PG is, how it works and how to put it to use.

What is propylene glycol?

Propylene glycol (1,2-propanediol) is a synthetic, colorless liquid with a thin, slightly syrupy texture. In formulation it does two main jobs:

• Solvent and carrier: it dissolves many ingredients that don't mix well with water alone, such as fragrance oils and some botanical extracts.
• Humectant: it attracts and holds moisture, helping products stay smooth and resist drying out.

Looking for a side-by-side comparison? See our guide to propylene glycol vs. vegetable glycerin.

Common uses

1. Soap making

PG is a popular addition to melt-and-pour and transparent soap recipes. It helps improve clarity, keeps soap bases fluid while you work and can help dissolve colorants and fragrance.

2. Lotions, creams and stick products

As a humectant and solvent, PG helps lotions and creams feel light and spread easily. It is also a common base in clear stick products, where it helps create a smooth glide.

3. Fragrance and extract bases

PG is widely used as a carrier for fragrance oils and botanical extracts in personal care formulas. It helps blend ingredients evenly into water-based products.

4. Room sprays and linen mists

A small amount of PG helps disperse fragrance or essential oils in water-based sprays so the blend stays mixed. Always follow essential oil safety guidance and dilution rates.

5. Humidor solutions

Many humidor and humidity-control setups use a PG and distilled water solution to help maintain steady humidity. Follow your device manufacturer's instructions for the right ratio.

Typical use levels

How much PG you use depends on the product and the feel you want. As a general starting point, many leave-on personal care formulas use PG at a few percent of the total formula, while soap bases and carriers may use more. Start low, test small batches and adjust from there.

Tips for working with PG

• Patch test new formulas. Some people are sensitive to PG on the skin.
• Measure by weight for consistent, repeatable batches.
• Keep it capped. PG absorbs moisture from the air.
• Store at room temperature, away from heat and direct sunlight.
• Keep out of reach of children and pets.

Compass Laboratory propylene glycol

Our propylene glycol is sourced in bulk as USP-grade material from a certified supplier and repackaged at our facility in Mena, Arkansas. Each bottle carries a lot number and expiration date for full traceability.

Shop the Propylene Glycol 2 Pack or get both with the Propylene Glycol & Vegetable Glycerin 2 Pack.

This article is for general educational purposes only. Compass Laboratory propylene glycol is sold as a formulation ingredient for personal care, DIY and industrial use and is not intended for food use.