Bath Salt Calculator
Make a bath salt blend by weight: set batch size and per-bath serving, plus carrier oil, fragrance and additive percentages, and the salts fill the rest. See how many baths it makes, in your browser.
Makes about
-
Your percentages add up to more than 100%, reduce them.
Show the math
Each add-in is a percentage of the batch; the salts fill the rest, and servings come from the batch size:
grams = batch × percent ÷ 100 · baths = ⌊batch ÷ per-bath⌋
Carrier oil makes a tub slippery, add a non-slip mat and keep oil modest. Essential oils have skin-safe bath limits and some aren't suitable for children or pregnancy; check each oil and disperse it (in the carrier or a solubiliser) rather than dropping it neat into water.
What this does
A bath salt calculator makes a blend by weight: set batch size and per-bath serving, plus carrier oil, fragrance, and additive percentages, and the salts fill the rest.
How to use it
- Enter the batch and per-bath size.
- Set each add-in percentage.
- Let the salts fill the balance.
- Read the grams and bath count.
How it works
Each add-in is a percentage of the batch; salts make up the rest. Keep carrier oil modest — it makes the tub slippery — and check each oil is bath-safe.
baths = batch ÷ per-bath (rounded down)
Understanding your result
Salts make up whatever the carrier oil, fragrance, and add-ins leave, and the figure to watch is the carrier oil: keep it modest, because too much makes the tub dangerously slippery and leaves a ring to scrub. Confirm each fragrance and botanical is bath-safe, and store the blend sealed, since salts readily draw moisture from the air and clump.
Example
A 1,000 g blend at 125 g per bath makes 8 baths.
Sources & methodology
Last updated .
Frequently asked questions
How are the amounts found?
Each add-in is a percentage of the batch (grams = batch \u00d7 percent \u00f7 100); salts make up the balance, and baths = \u230abatch \u00f7 per-bath\u230b.
Is carrier oil safe in the tub?
Oil makes a tub slippery \u2014 keep it modest and use a non-slip mat. It also helps disperse essential oils so they don\u2019t sit neat on the water.
Are all essential oils bath-safe?
No \u2014 oils have skin-safe bath limits and some aren\u2019t suitable for children or pregnancy. Check each oil and disperse it rather than dropping it neat into water.
Do you store anything?
No \u2014 every calculation runs locally in your browser.
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