Work out the batch before you pour it.
The math behind handmade candles, soap, bath bombs, perfume and resin. Work out fragrance, lye, ratios and pricing before you make a batch.
31 calculators across 5 crafts. Free, nothing saved.
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All calculators → 6 tools Candles The numbers behind a clean pour: how much wax a vessel takes, a safe fragrance load, the right wick, and what each candle costs to make. Open → 9 tools Soap Every figure a soaper needs before the stick blender comes out, lye and superfat, water discount, recipe resizing, bar yield and cost per bar. Open → 3 tools Bath bombs Get the fizz right the first time: the ratio and why it is 1:2, how much mix your mold takes, which additives do anything, and what a bomb costs to make. Open → 7 tools Perfume Everything before the first bottle: what to buy, how strong to make it, how to balance a blend so it lasts past lunchtime, and why it smells of alcohol for the first two days. Open → 6 tools Resin How much epoxy a project actually needs, split into resin and hardener in milliliters and grams, with your resin's own pour depth ceiling checked, because exceeding it is a heat hazard rather than a slow cure. Open →
Popular calculators
Browse all →Candles Wax weight Wax for any vessel, by fill line and candle count. Soap Lye & superfat NaOH or KOH for any oil blend, with superfat. Bath bombs Recipe builder Ratio, additives, butters, scent and cost per bomb. Perfume Dilution and blending Oil to alcohol at any strength, with the note split checked. Resin Epoxy calculator Volume by shape and depth, split into resin and hardener, with the depth ceiling checked.
Batch logs & worksheets
Printable logs for your workspace. Note what you poured, what it cost and how it turned out. Buy once, print whenever.
Why makers trust the numbers
Nothing is saved
No account. No email sign-up. No pop-ups. Type your numbers, get your answer, close the tab.
The math is shown
Every calculator shows its formula and what it assumes, so you can check the numbers yourself.
One set of numbers
Every figure comes from the same data, so our guides and calculators always agree.