Glass Blowing Calculators
Free online glass blowing calculators.
Calculate annealing schedules, color mixing ratios, glass weight, and more for glassblowers.
Glass Mass and Volume Calculator (COE 33, 96, 104)
Calculate glass weight from volume or volume from weight, by COE type. Soft glass, borosilicate, and lead crystal density values included.
Glass COE Compatibility Calculator
Check coefficient of expansion (COE) compatibility between glasses for fusing and blowing. Avoid cracking from mismatched COE in soft and borosilicate glass.
Glass Weight Calculator
Calculate glass piece weight from shape and dimensions. Covers soda-lime, borosilicate, and lead crystal for cylinders, spheres, and flat slabs.
Glass-Blowing Frit Coverage Calculator
Calculate frit weight needed to cover a glass-blowing piece. Enter surface area and frit grade to get grams required for full or accent coverage patterns.
Glass Blowing Gather Weight Calculator
Calculate molten glass gather weight from finished piece volume, glass density, and waste factor. For studio glassblowers planning blanks and gathers.
Glass Annealing Schedule Calculator
Calculate annealing hold time, soak temp, and cooling ramp from glass thickness and COE. Returns kiln schedule for borosilicate, soda-lime, and fused glass.
Glass Color Mixing Calculator
Calculate glass color mixing ratios for frits and rods to achieve target hues. Returns blends by weight based on additive and subtractive glass color mixing.
Glass Kiln Casting Schedule Calculator
Generate a kiln firing schedule for glass casting. Covers ramp rates, hold times, and annealing for pate de verre and lost wax.
Glassblowing Pipe Size Calculator
Find correct glassblowing pipe size from gather weight and technique. Covers small, medium, and large gathers for vessels, paperweights, and sculptures.