Glass Size Calculator — Glazing for Picture Frames
Calculate the glass or acrylic glazing size needed for your frame.
Inside width of the frame rebate
Inside height of the frame rebate
Total clearance (1mm each side)
How We Calculate This
Glass size = Frame rebate size - Clearance
Weight is calculated from area, thickness (2 mm standard) and material density. Glass weighs about 2.5 kg/m² per mm thickness; acrylic weighs about 1.19 kg/m² per mm.
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates. Always verify quantities before purchasing materials.