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Glaze Quantity Calculator

Glaze needed for a batch of pots, the dry glaze powder to make it, and the bucket size to mix it in.

Glaze is bought as a dry powder, mixed with water into a slurry, and used by dipping, pouring or spraying. The quantity question has three answers and people usually only work out one of them: the liquid needed to cover the pots, the dry powder that liquid contains, and how big a bucket has to be to dip the largest piece. This calculator gives all three, plus a coverage figure in grams of dry glaze per piece.

At a glance

What you enter
Glazed surface of one piece, Number of pieces, How the glaze goes on, Coats, Slurry specific gravity, Dry glaze in the slurry by weight, Reserve left in the bucket, Price of dry glaze per kilogram, Height of the largest piece
What you get
Total surface to glaze, Total surface to glaze, Slurry to cover the batch, Weight of the slurry used, Dry glaze in the slurry used, Dry glaze to buy, Slurry to mix, Dry glaze per piece, Dry glaze per square metre, Cost of the dry glaze, Glaze cost per piece, Glaze cost per hundred pieces, Working depth the bucket needs, Bucket size to buy, Water in the slurry
Formula shown
Yes, every step, right below your results.
Cost and privacy
Free, no account needed, and nothing you type is stored.

See worked examples โ†“ Read the FAQ โ†“ Share this calculator โ†“

Every surface that gets glaze: outside, inside a bowl, the base if it is not wiped.

How the glaze goes on

Dipping is the most economical way to cover a repeated form. Spraying loses glaze to the booth, brushing uses the least volume but needs more coats.

One for a dipped glaze at working thickness, two or three for a brushed one.

A dipping glaze mixed at working thickness is usually about 1.4 to 1.6.

Roughly 30 to 40 percent for a dipping glaze. Check the supplier data for the recipe you use.

The glaze that stays in the bucket between batches. Twenty percent is a fair working figure.

Optional. Used for the cost per piece.

Used for the bucket size. Leave at zero if you do not need it.

Reset

Results are estimates for general information only, always verify with a professional or official source before acting on them.

How to use the Glaze Quantity Calculator

  1. 1 Enter Glazed surface of one piece (sq cm), Every surface that gets glaze: outside, inside a bowl, the base if it is not wiped.
  2. 2 Enter Number of pieces
  3. 3 Enter How the glaze goes on, Dipping is the most economical way to cover a repeated form. Spraying loses glaze to the booth, brushing uses the least volume but needs more coats.
  4. 4 Enter Coats, One for a dipped glaze at working thickness, two or three for a brushed one.
  5. 5 Enter Slurry specific gravity, A dipping glaze mixed at working thickness is usually about 1.4 to 1.6.
  6. 6 Enter Dry glaze in the slurry by weight (%), Roughly 30 to 40 percent for a dipping glaze. Check the supplier data for the recipe you use.
  7. 7 Enter Reserve left in the bucket (%), The glaze that stays in the bucket between batches. Twenty percent is a fair working figure.
  8. 8 Enter Price of dry glaze per kilogram, Optional. Used for the cost per piece.
  9. 9 Enter Height of the largest piece (cm), Used for the bucket size. Leave at zero if you do not need it.
  10. 10 Press Calculate. You get Total surface to glaze, Total surface to glaze, Slurry to cover the batch, Weight of the slurry used, Dry glaze in the slurry used, Dry glaze to buy, Slurry to mix, Dry glaze per piece, Dry glaze per square metre, Cost of the dry glaze, Glaze cost per piece, Glaze cost per hundred pieces, Working depth the bucket needs, Bucket size to buy, Water in the slurry, and every intermediate step stays visible under "How is this calculated?"
  11. 11 Change one number at a time to see what moves the result, that is usually the most useful thing a calculator can tell you.

Worked examples

Real numbers run through this calculator. Open any example to load it into the form above and change it.

A hundred mugs, dipped

300 square centimetres of glazed surface per mug, one dip, 40 percent solids, a 20 percent bucket reserve.

You enter

Glazed surface of one piece
300 sq cm
Number of pieces
100
How the glaze goes on
1
Coats
1
Slurry specific gravity
1.50
Dry glaze in the slurry by weight
40%
Reserve left in the bucket
20%
Price of dry glaze per kilogram
$18.00
Height of the largest piece
14 cm

You get

Total surface to glaze
30,000.00 sq cm
Total surface to glaze
3.00 sq m
Slurry to cover the batch
0.60 L
Weight of the slurry used
900.00 g
Dry glaze in the slurry used
360.00 g
Dry glaze to buy
0.43 kg
Slurry to mix
0.72 L
Dry glaze per piece
3.60 g
Dry glaze per square metre
120.00 g
Cost of the dry glaze
$7.78
Glaze cost per piece
$0.08
Glaze cost per hundred pieces
$7.78
Working depth the bucket needs
18.00 cm
Bucket size to buy
5.00 L
Water in the slurry
540.00 g

3 square metres needs 600 ml of slurry, which is 900 grams of slurry and 360 grams of dry glaze. With the reserve, buy 0.43 kg, and the bucket needs a 19 cm working depth.

Open this example in the calculator โ†’

Twenty large bowls, poured

A thousand square centimetres per bowl, a 1.45 specific gravity.

You enter

Glazed surface of one piece
1,000 sq cm
Number of pieces
20
How the glaze goes on
2
Coats
1
Slurry specific gravity
1.45
Dry glaze in the slurry by weight
38%
Reserve left in the bucket
25%
Price of dry glaze per kilogram
$18.00
Height of the largest piece
12 cm

You get

Total surface to glaze
20,000.00 sq cm
Total surface to glaze
2.00 sq m
Slurry to cover the batch
0.50 L
Weight of the slurry used
725.00 g
Dry glaze in the slurry used
275.50 g
Dry glaze to buy
0.34 kg
Slurry to mix
0.63 L
Dry glaze per piece
13.78 g
Dry glaze per square metre
137.75 g
Cost of the dry glaze
$6.20
Glaze cost per piece
$0.31
Glaze cost per hundred pieces
$30.99
Working depth the bucket needs
16.00 cm
Bucket size to buy
5.00 L
Water in the slurry
449.50 g

2 square metres at 1 litre per 4 needs 500 ml, which is 725 grams of slurry and 276 grams of powder, so about 0.34 kg with the reserve.

Open this example in the calculator โ†’

A brushed decorative layer

Fifty small tiles with 120 square centimetres each, two coats.

You enter

Glazed surface of one piece
120 sq cm
Number of pieces
50
How the glaze goes on
4
Coats
2
Slurry specific gravity
1.50
Dry glaze in the slurry by weight
42%
Reserve left in the bucket
30%
Price of dry glaze per kilogram
$22.00
Height of the largest piece
10 cm

You get

Total surface to glaze
6,000.00 sq cm
Total surface to glaze
0.60 sq m
Slurry to cover the batch
0.40 L
Weight of the slurry used
599.40 g
Dry glaze in the slurry used
251.75 g
Dry glaze to buy
0.33 kg
Slurry to mix
0.52 L
Dry glaze per piece
5.03 g
Dry glaze per square metre
419.58 g
Cost of the dry glaze
$7.20
Glaze cost per piece
$0.14
Glaze cost per hundred pieces
$14.40
Working depth the bucket needs
14.00 cm
Bucket size to buy
5.00 L
Water in the slurry
347.65 g

Brushing uses the most slurry per square metre but needs two coats, so the batch still comes to about 0.4 litres and 0.3 kg of powder.

Open this example in the calculator โ†’

Frequently asked questions

How much glaze do I need for a batch of pots?
Work out the glazed surface area first. A hundred mugs with 300 square centimetres each is 3 square metres, which at a dipping coverage of 1 litre per 5 square metres is 600 millilitres of slurry. At a specific gravity of 1.5 that slurry weighs 900 grams, and at 40 percent solids it contains about 360 grams of dry glaze. Add a reserve for the bucket, and half a kilogram of powder covers the batch comfortably.
How many square metres does a litre of glaze cover?
About 4 to 6 square metres at dipping thickness for a glaze mixed at working specific gravity, so 1 litre per 5 square metres is the working figure. Spraying reaches about 7 square metres because less liquid lands on the piece, though much of it is lost to the booth. Pouring uses more, nearer 4 square metres per litre, and brushing covers the least area per litre but usually needs two or three coats.
How big a bucket do I need?
Big enough to submerge the largest piece with two or three centimetres of glaze above it and to spare at the sides, plus freeboard so the glaze closes back over the piece as you lift it out. In practice that means a bucket considerably larger than the volume of glaze the batch consumes, which is why most potters keep one bucket per glaze sized for their biggest form and top up the level rather than mixing fresh each time.
Why is the dry glaze weight less than the slurry weight?
Because a dipping glaze is mostly water. At a specific gravity of 1.5 the slurry is roughly 60 to 70 percent water by weight, with the rest being the dry glaze solids. That is why 600 millilitres of slurry, which weighs 900 grams, contains only about 360 grams of powder. The powder percentage varies with the recipe and with how thick you mix it, so use the figure for your own glaze rather than a generic one.
Is a glaze recipe a safety matter?
Yes. Glaze materials are fine powders, and some contain silica, feldspar or metal oxides that carry a respiratory hazard, so mixing dry glaze needs proper protection and ventilation as set out on the supplier safety data sheet. This tool works out quantities only and gives no recipe or mixing instruction. Follow the data sheet for the materials you use, and check the fired result is suitable for food contact if the piece is domestic ware.

More money questions answered โ†’

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