Epsom Salt Foot Soak Calculator
Get the right amount of Epsom salt for your foot soak. Enter how much water your basin holds and the tool gives you the dose in grams, cups and tablespoons at the standard ratio — plus safe temperature and timing.
The ratio this tool uses
The widely used home guideline is about half a cup of Epsom salt (magnesium sulphate) per gallon of warm water — roughly 30 grams per litre. The calculator scales that to your basin and also shows cups and tablespoons (1 level cup of Epsom salt is about 240 g; 1 tablespoon is about 18 g). There is no benefit to a stronger brine; it just dries the skin faster.
| Water | Epsom salt | Approx. measure |
|---|---|---|
| 2 litres | ~60 g | ~¼ cup |
| 4 litres (typical basin) | ~120 g | ~½ cup |
| 1 US gallon (3.8 L) | ~115 g | ~½ cup |
| 6 litres | ~180 g | ~¾ cup |
How to soak safely
- Use warm, not hot water — about 37–39 C (98–102 F). Test with your elbow or a thermometer; never trust your feet alone.
- Stir the salt until it dissolves, then soak for 10–20 minutes. Longer does not add benefit and dries the skin.
- Dry thoroughly, especially between the toes, and apply moisturiser (avoiding between the toes) to counter the drying effect.
- Soak at most a few times a week.
Epsom soaks are soothing for tired, achy feet and can soften hard skin before filing, but the evidence that magnesium is absorbed through the skin in meaningful amounts is weak — treat the comfort, warmth and downtime as the real benefit. For more blends see our foot soak recipes.
Frequently asked questions
- How much Epsom salt for a foot soak?
- About half a cup per gallon of warm water, or roughly 30 grams per litre. A typical 4-litre foot basin needs about 120 g (half a cup).
- How long should I soak my feet?
- Ten to twenty minutes is plenty. Soaking longer does not add benefit and can dry out and crack the skin.
- Can I soak my feet in Epsom salt every day?
- Occasional soaks are fine for most people, but daily soaking tends to dry the skin. A few times a week is a sensible maximum, and always moisturise afterwards.
- Is an Epsom salt foot soak safe for diabetics?
- Generally no. People with diabetes, neuropathy or poor circulation should avoid foot soaks because reduced sensation can hide burns and soaking raises infection risk. Ask your care team first.