Glaze Recipe Batch Calculator

A glaze batch calculator turns a percentage recipe into real weights: multiply your base batch weight by each ingredient’s percentage and divide by 100. Additions such as colorants or opacifiers are figured the same way and weighed on top of the base. Enter your recipe below to get grams, kilograms, ounces or pounds.

How to use the glaze recipe batch calculator

1. Type each base ingredient’s name and percentage. A standard base adds up to 100. Use “+ Add ingredient” to add rows and “×” to remove one.
2. Enter any additions (colorants, opacifiers, variegating materials) as a percentage of the base.
3. Enter the base batch weight and choose your unit. This is the dry weight of a 100-part base, before additions.
4. Choose whether to normalize a base that doesn’t total 100 or to use the numbers exactly as entered.
5. Press “Calculate batch”. If something is missing or invalid, such as an empty base, a message appears in the result box. Otherwise you get a printable weighing checklist. Print it and tick each box on the paper sheet once that material is weighed and checked.

How glaze batch math works

Glaze recipes are usually written as a base plus additions. The Digitalfire Reference Library describes the base as the materials that fire to produce the glass, while additions add color, opacity and variegation. The base is written to total 100, and each addition is a percentage of that 100-part base. Because of this, a recipe with additions totals more than 100.

The calculator uses these formulas:

• Base ingredient weight = batch weight × ingredient % ÷ 100
• Addition weight = batch weight × addition % ÷ 100 (weighed on top of the base)
• For a normalized or 100-based recipe: total dry weight = batch weight × (100 + sum of additions) ÷ 100
• With normalization off and a base that isn’t 100: total dry weight = batch weight × (base total + sum of additions) ÷ 100

Here is an example for a 1,000 g base batch with a 10% opacifier addition:

Scaling a glaze recipe and converting percentages to grams

Scaling a recipe. Because every weight is proportional, you scale a glaze recipe just by changing the batch weight. A 100 g test batch and a 10 kg bucket batch use the same percentages. Only the base weight you type in changes.

Percentage to grams. With a 100 g base batch, each percentage equals the same number of grams, which makes test tiles easy to weigh. For any other size, the calculator does the multiplication and shows grams to one decimal place.

Recipes that don’t total 100. Some published recipes total 98 or 103 because of rounding or editing. Digitalfire notes that a recipe can be retotalled based on the base or on the full recipe, and this tool retotals on the base.

When you choose to normalize, the calculator multiplies each base percentage by 100 ÷ (base total), so a base of 45 + 45 becomes 50 + 50. Additions stay as entered. If you choose not to normalize, the percentages are used exactly as typed and the batch weight is treated as a 100-part reference. In that case the actual base subtotal differs from the batch weight. For example, a base of 45 + 45 with a 500 g batch weighs 450 g. A warning shows the real base total.

Imperial units. If you choose ounces or pounds, the weights appear in that unit. The total is also given in grams, using the exact definitions 1 oz = 28.349523125 g and 1 lb = 453.59237 g.

Methodology & sources

The calculator uses no material constants. It applies proportional math based on the base-plus-additions convention and exact unit definitions. It does not judge whether a glaze will melt, fit your clay or be food-safe.

• Digitalfire Reference Library – Batch recipe: the base and additions convention, and retotalling on the base
• Wikipedia – Pound (mass): 1 lb = exactly 0.45359237 kg = 16 oz
• Wikipedia – Ounce: 1 oz = exactly 28.349523125 g

Last updated: November 2026

FAQ

How do I convert glaze recipe percentages to grams?

Multiply your base batch weight by each ingredient’s percentage and divide by 100. For a 1,000 g base, an ingredient at 30% weighs 300 g.

How are glaze additions like colorants calculated?

By the usual convention, additions are a percentage of the 100-part base and are added on top of it. A 10% addition to a 1,000 g base is 100 g, so the total dry weight becomes 1,100 g.

What if my glaze recipe base doesn’t add up to 100?

You can normalize it: each base percentage is multiplied by 100 divided by the base total, so the proportions stay the same but the base sums to exactly 100. The calculator does this when you choose the normalize option and shows the adjusted percentages.

Does the batch weight include the additions?

No. The batch weight is the dry weight of a 100-part base, and additions are weighed on top. If you turn normalization off and the base does not total 100, the batch weight is treated as the 100-part reference, so the actual base subtotal will be higher or lower than the number you entered.

Which unit conversions does the calculator use?

It uses the exact definitions 1 oz = 28.349523125 g and 1 lb = 453.59237 g (16 oz). Because the math is proportional, every ingredient is shown in the unit you chose, with the total also given in grams.

Related guides

• How to Mix Dry Glaze Powder for Ceramics
• Is Reactive Glaze Safe for Pottery?
• How to Glaze Pottery for an Even, Finished Surface