Salt Dough Calculator

Background.

Salt dough is the craft-table recipe that needs no scale: two parts plain flour, one part table salt and one part water, by volume. Michigan State University Extension gives it as 1 cup of flour, ½ cup of salt and ½ cup of water, rolled a quarter inch thick and dried at 250 °F for two to three hours, and N.C. Cooperative Extension prints the same blend.

Scaling it is easy until the numbers turn awkward: ornaments for three classes of children, a project specified in grams, or a salt canister that runs dry at three-quarters of a cup. You can start from the flour you want to use, the salt you have or the weight of raw dough you need, and all three ingredients come back in cups and in grams, using King Arthur's chart weights for flour and salt and the exact US cup for water. A cup of table salt, at 288 g, weighs well over twice a cup of flour at 120 g.

Each result also states the sodium in the batch, because salt dough is a craft material and not food.

What is salt dough calculator?

Salt dough is a modelling material of flour, salt and water that hardens by drying slowly in a low oven, not by baking like bread. The salt defines it: at half the flour's volume it comes to 120% of the flour's weight, against roughly 2% in a bread dough, and it dries to a hard, pale body that takes paint. Because the recipe is a volume ratio, any cup or mug works as the measure if you use the same one for all three ingredients.

How to use this calculator.

1. 01Choose what you know: the flour you want to use, the salt you have left, or the weight of raw dough a project calls for.
2. 02For flour or salt, choose cups or grams and enter the amount. Grams are turned into cups first, at 120 g per cup of flour and 288 g per cup of table salt; a dough weight is always in grams.
3. 03Enter the thickness you will roll to. It changes only the oven guidance, never the quantities.
4. 04Mix the flour and salt dry, then add the water a little at a time and stop when the dough is firm and no longer sticky; the water figure is the most you should need.

The formula.

Whatever you enter is divided by its own share of the ratio to give a scale factor: flour cups ÷ 2, salt cups ÷ 1, or a target dough weight ÷ 764.12 g, the weight of one batch of 2 cups flour, 1 cup salt and 1 cup water. Each ingredient is its ratio part × the scale. Flour weighs 120 g a cup; salt weighs 18 g a tablespoon × 16 tablespoons = 288 g a cup; water is 236.5882365 mL a cup, the exact US definition, × 0.99802 g/mL, the USGS density at 70 °F, giving 236.12 g. Sodium is cups of salt × 48 teaspoons × 2.3 g, from the FDA's statement that a teaspoon of table salt holds about the 2,300 mg daily limit. Salt is always 120% of the flour's weight and water 98.3832%. For pieces up to a quarter inch thick the oven guidance quotes the published 250 °F (121 °C) for two to three hours; for thicker pieces it gives only the temperature and the instruction to bake until completely dry.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Michigan State University Extension (Carrie Shrier). "The joy of homemade gifts: Salt-dough ornaments", article dated 11 December 2025; retrieved 30 July 2026. The primary source for the ratio this calculator scales and for every oven figure on the page: "1 cup flour, 1/2 cup salt, 1/2 cup water"; "Preheat oven to 250 degree Fahrenheit"; "Roll dough to 1/4-inch thickness"; "Bake for 2-3 hours or until completely dry"; and the finishing note, "For durability, seal with clear acrylic varnish to protect against moisture."
2. [2]N.C. Cooperative Extension, Edgecombe County. "Crafts" activity packet, 2020; retrieved 30 July 2026. The independent confirmation of the blend: the same 1 cup flour, 1/2 cup salt and 1/2 cup water, and the same 250 F oven, published by a different land-grant extension service and credited to Design Mom. Access: open, though the PDF's text layer did not extract on direct fetch and the figures were read from the indexed record.
3. [3]King Arthur Baking Company. Ingredient Weight Chart, current revision; retrieved 30 July 2026. Source of the two solid-ingredient densities: "All-Purpose Flour 1 cup 4 1/4 oz 120 g" and "Salt (table) 1 tablespoon 2/3 oz 18 g", hence 288 g per cup. Also the kosher-salt figures this page cites as a warning against substitution — Diamond Crystal 8 g per tablespoon, Morton's 16 g — and the 227 g water cup that this page deliberately does not use.
4. [4]National Institute of Standards and Technology. NIST Special Publication 811, 2008 edition — Guide for the Use of the International System of Units (SI). Table B.6 US customary capacity factors: cup = 236.5882365 mL, tablespoon = 14.78676478125 mL, teaspoon = 4.92892159375 mL, and therefore the exact identities of 16 tablespoons and 48 teaspoons to the cup that convert King Arthur's per-tablespoon salt figure and the FDA's per-teaspoon sodium figure to a per-cup basis without rounding.
5. [5]U.S. Geological Survey, Water Science School. "Water Density", page last updated 5 June 2018; retrieved 30 July 2026. Source of the water density used for the weight readout: 0.99802 g/cm3 at 70 F (21 C), alongside 1.00000 g/cm3 at 4 C and the page's own caution that "the exact density of water is not really 1 g/ml, but rather a bit less (very, very little less), at 0.9998395 g/ml at 4.0 degrees Celsius."
6. [6]U.S. Food and Drug Administration. "Sodium in Your Diet", current revision; retrieved 30 July 2026. The single sentence behind both sodium figures on this page: adults should limit sodium to "less than 2,300 mg per day - that's equal to about 1 teaspoon of table salt". The batch's sodium load is 2.3 g per teaspoon times 48 teaspoons per cup of salt, and the multiple printed in the safety line is that total divided by the same 2,300 mg limit.
7. [7]Pet Poison Helpline. "Salt" and "Play Dough (Homemade)" poison monographs, current revision; retrieved 30 July 2026. Salt-dough exposure is listed explicitly among the routes to salt toxicity — "consuming handmade salt-dough ornaments or homemade salt-play dough" — with signs of "gastrointestinal distress (e.g., vomiting, diarrhea), neurological signs (e.g., stumbling gait, disoriented behavior, tremor, seizure, collapse), and death", the statement that ingestion "has resulted in fatalities", the warning that salt and salt water must never be used to induce vomiting, and the helpline number (855) 764-7661. No numeric toxic dose is published by this source, and none is stated on this page.
8. [8]ASPCA. "Crafting with Care: Pet Safety Tips for Holiday Arts and Crafts", current revision; retrieved 30 July 2026. The mechanism behind the warning: "Salt dough is typically made with flour, water, and salt that is then baked until dried. These ornaments can be easily confused for a salty dog treat by your pet", with hypernatremia progressing to seizures or death if untreated, and the Animal Poison Control Center number (888) 426-4435.