Magnesium oil is a simple solution of magnesium chloride flakes dissolved in water, and you can make it at home in about five minutes. The standard ratio is equal parts magnesium chloride flakes and distilled water by volume. Despite the name, it’s not actually an oil. The concentrated brine just feels slippery on skin, which is how it got the nickname.
What You Need
The ingredient list is short: magnesium chloride flakes and distilled water. That’s it. You’ll also want a small saucepan, a glass or HDPE plastic spray bottle, and a spoon for stirring.
Use distilled water rather than tap water. Tap water contains chlorine, fluoride, and trace minerals that can react with the magnesium chloride and shorten the shelf life of your finished product. Distilled water is the standard in cosmetics manufacturing for exactly this reason. It also reduces the chance of bacterial growth in the solution over time. You can find it at any grocery store for about a dollar per gallon.
For the flakes, look for magnesium chloride hexahydrate specifically. These are sold as “magnesium bath flakes” or “magnesium flakes” online and in health stores. Some brands source their flakes from the ancient Zechstein seabed in the Netherlands, which is marketed as a purity indicator, though any food-grade magnesium chloride flakes will work.
Step-by-Step Instructions
Start by measuring out equal amounts of flakes and distilled water. A half cup of each is a good first batch, yielding roughly four ounces of magnesium oil.
Heat the water in a saucepan until it’s warm but not boiling. You want it hot enough to dissolve the flakes quickly, somewhere around the temperature of hot tap water. Boiling is unnecessary and can make the solution spatter. Once the water is warm, add the magnesium chloride flakes and stir until they’re completely dissolved. This takes about one to two minutes. The liquid will look clear and feel slightly oily between your fingers.
Let the solution cool to room temperature, then pour it into a spray bottle. Glass bottles are a popular choice for home use, but HDPE plastic (the type marked with a #2 recycling symbol) is also safe and won’t leach chemicals into the solution. Either way, store it in a cool area away from direct sunlight.
Adjusting the Concentration
The 1:1 ratio produces a fairly concentrated solution, which is what most people start with. If you find it too irritating on your skin (more on that below), you can dilute it. Some people shift to a 50% concentration after using it for a while, using one part flakes to two parts water. There’s no single “correct” strength. The full-concentration version simply delivers more magnesium per spray.
How to Apply It
Spray the solution directly onto your skin, targeting areas like your arms, legs, or stomach where it absorbs most comfortably. Avoid freshly shaved skin, broken skin, or sensitive areas like your face, as the concentrated salt solution will sting. Many people apply it after a shower when pores are open, then let it sit for 20 to 30 minutes before rinsing off if desired.
Before using it broadly, do a patch test. Spray a small amount on the inside of your forearm, leave it for 24 hours, and check for any rash, irritation, or persistent discomfort. If your skin reacts, wash the area with gentle soap and water.
Why It Tingles (and How to Reduce It)
A tingling or mild stinging sensation is extremely common the first few times you use magnesium oil, especially at full concentration. This happens because the high-salt solution pulls moisture from skin cells through osmosis, creating that prickly feeling. It’s not a sign of deficiency, despite what some wellness sites claim. It’s just concentrated salt on skin.
The sensation typically fades after a few minutes and tends to decrease with regular use as your skin adjusts. If it bothers you, dilute your batch with more distilled water, apply a moisturizer over the area after the oil dries, or simply rinse it off after 20 minutes. Applying to well-hydrated skin rather than dry skin also helps.
How Well Does It Actually Work?
This is where the picture gets complicated. Magnesium oil is widely promoted for raising magnesium levels through the skin, but the scientific evidence is limited and mixed. Skin is designed to be a barrier, not an absorption surface. Magnesium ions in solution are surrounded by water molecules, making them roughly 400 times larger than their bare form, which makes it very difficult for them to pass through skin’s outer layer.
A small study of nine patients using magnesium oil for 12 weeks found an average 59.7% increase in magnesium levels measured in hair, with individual results ranging wildly from a slight decrease to a 262% increase. Another study of 19 people bathing in magnesium salt solution for seven days showed modest increases in blood magnesium levels. And a pilot study of 25 participants using a magnesium cream for two weeks found a small increase in serum magnesium that was only statistically significant in a subgroup of non-athletes.
A 2017 review published in the journal Nutrients examined all available evidence and concluded that transdermal magnesium absorption is “scientifically not yet proven.” Hair follicles and sweat glands, which offer the most plausible route for absorption, make up only 0.1% to 1% of the skin’s surface. The researchers specifically warned against relying on topical magnesium if you have a genuine deficiency that needs treatment. Oral supplements and dietary sources remain far better supported for actually raising your magnesium levels.
That said, many people report that magnesium oil helps with muscle soreness and relaxation. Whether that comes from meaningful absorption, a placebo effect, or simply the act of massaging a warm solution into tired muscles is an open question.
Storage and Shelf Life
Homemade magnesium oil keeps well because the high salt concentration discourages bacterial growth. Stored in a sealed container away from heat and direct sunlight, it should last for several months without any preservatives. If it develops an off smell or visible cloudiness, make a fresh batch. Using distilled water from the start is the single best thing you can do to maximize shelf life.
Who Should Be Cautious
People with reduced kidney function should be careful with any form of magnesium supplementation, including topical. Healthy kidneys efficiently clear excess magnesium from the blood, but when kidney function declines, magnesium can accumulate. Dangerously high magnesium levels are rare and usually only seen in people with chronic kidney disease who are also taking magnesium-containing medications, but the risk exists. If you have kidney problems, talk with your doctor before adding magnesium oil to your routine.