Learning how to measure for custom cut glass takes about ten minutes and saves the one mistake that cannot be undone: a piece cut precisely to the wrong number. Custom glass is made to the dimensions you submit, so the tape measure is doing more work than the checkout.
Royalty Mirror is a custom glass manufacturer handling glass table tops, mirrors, shower doors, insulated glass and custom cut glass with free shipping, and its order form asks for the same seven things every time. This guide walks through each one in the order it is asked, using real order records as reference points.
Step 1: choose the shape
Every documented order in the set is a rectangle, which includes squares. Start here because shape decides how many measurements you owe: a rectangle needs a length and a width, and nothing else.
If the piece is replacing existing glass, trace the old piece onto cardboard before you measure. If it is covering furniture, decide first whether you want the glass flush with the edge or slightly inset, because that decision changes every number that follows.
Step 2: get the dimensions right, down to sixteenths
This is where accuracy pays. Royalty Mirror records dimensions in inches and fractions, and real orders are rarely round: 59 inches and 5/8 by 20 inches, 65 inches and 15/16 by 20 inches, 63 inches and 1/4 by 16 inches and 5/8, 29 inches and 3/4 by 14 inches and 1/2.
Three habits prevent most errors:
- Measure length and width in at least two places each. Old furniture is rarely square.
- Write the fraction down immediately, not the decimal in your head.
- If two measurements disagree, use the smaller one so the glass drops in rather than jams.
Then read the numbers back off the order form before paying. That 15/16 in a real order is exactly the kind of detail that gets typed as 15/8 at midnight.
Step 3: pick the glass type
Clear glass is the default across nearly every documented order. Black glass appears as the alternative, priced the same on equivalent sizes: a 36 by 12 inch and 9/16 piece is $149.75 in black at 9.68 lbs.
Choose clear when you want the surface underneath to show, such as a protective top over wood. Choose black when the glass is the finish, such as a shelf where you would rather not see everything resting on it.
Step 4: choose thickness, and understand the weight
Thickness is the decision that quietly determines whether you can lift the thing. The documented orders show a clear pattern:
- 1/4 inch tempered on virtually every table top and replacement pane
- 3/16 inch tempered on a small shelf, 10 by 18 inches and 3/8, weighing 3.13 lbs at $61.59
- 3/8 inch on the shower door, at 44 by 70 inches
Weight scales fast at 1/4 inch. A 19 inch and 3/4 by 24 inch top is 10.21 lbs, a 34 by 34 inch square is 25.89 lbs, and a 78 by 42 inch top reaches 73.38 lbs. Anything past roughly 25 lbs is a two-person lift, and that changes how you plan installation day.
Step 5: pick the edge
Flat polished edge appears on every documented order, from the $4.99 sample square to the $1,425.40 dining top. It is the safe default and the reason a custom piece looks finished rather than cut.
Step 6: decide on corner finish
Most orders record no corner finish, which means square corners. The exception is the largest top in the set, a 78 by 42 inch rectangle specified with a 6 inch round corner on corners A, B, C and D.
Use that as your rule of thumb. Square corners are fine on a shelf or anything against a wall. On a big top at hip height in an open room, round them. Note also that the form labels corners A, B, C and D individually, so you can round only the two that sit in the walkway.
Step 7: check the price and the sample
The price is calculated from everything above, which is why two similar tops can differ sharply: $197.41 for 64 inches and 3/4 by 15 inches and 3/4, versus $350.24 for 65 inches and 15/16 by 20 inches. Depth costs more than length.
Before a large order, spend $4.99 on the 3 by 3 inch square in 1/4 inch tempered clear glass with a flat polished edge. At 0.20 lbs it ships easily and it answers the questions a photo cannot.
Measuring for a shower door
Shower doors add their own questions, and the documented order shows exactly which. It records the shower type as bypass sliding, the layout as linear bypass sliding, the dimensions as 44 inches wide by 70 inches high, clear glass at 3/8 inch, matte black hardware, a 24 inch towel bar handle, no ceiling attachment, and walls confirmed not out of plumb.
That out-of-plumb question is the one to take seriously. Hold a level against each wall of the opening before you answer it, because a door cut for square walls in a bathroom that is not square will not sit right. Measure the width at the top, middle and bottom of the opening, and note the height on both sides.
The form also asks about a Royalty Shield option as a yes or no. The order record does not spell out what it includes, so ask before checkout rather than assuming.
Before you click order
- Re-measure everything once, cold, on a different day.
- Confirm the fraction, not just the whole inches.
- Check the listed weight and arrange a second pair of hands if needed.
- Confirm shape, glass type, thickness, edge and corner finish on the summary.
Doing the sequence in that order also forces you to plan where the piece lives, which is half of any home project. Our home organization starter kit and the room-by-room decluttering guide are useful if the glass is part of a bigger reset rather than a one-off fix.
When your numbers are confirmed, enter them at Royalty Mirror and the price calculates from your spec.
Common questions
What if my two width measurements disagree?
Use the smaller measurement. Glass cut to the larger number will not fit the narrower point of the opening.
How heavy is custom glass?
From real orders: 0.20 lbs for a 3 by 3 inch square, 3.13 lbs for a 3/16 inch shelf, 25.89 lbs for a 34 by 34 inch top and 73.38 lbs for a 78 by 42 inch top.
Can I order in Spanish?
At least one order record is written in Spanish, listing cristal transparente, vidrio templado de 1/4 and borde plano pulido, so the configurator supports it.
Ready to submit your measurements? Configure the piece at Royalty Mirror.