Optimal build
Dining table 36" round
914 mm dia · 12 mm tempered · 4-leg stand
19.7 kg
· 49 kg cap
✕ Guess: 10 mm annealed on a 4-leg stand — one lean and the glass flexes
✓ Spec: 12 mm tempered on 4 legs: 27 kg capacity, 23 kg weight, safe overhang
Tops That Sit Right — Weight, Thickness, Overhang
Glass Table Top Weight & Thickness Calculator
Enter the shape, dimensions, thickness and support type — read the panel weight in kilograms and pounds, the recommended thickness for the load, whether the overhang clears the pedestal rule, and whether a desk point-load passes. Six scenario builds show the spec that works before you order the glass.
🍽️ Round · rect · oval⚖️ Plate-bending model📐 Overhang rule & desk load
Shape sets the area — support sets the thicknessPhoto: UnsplashGlass Table Top Weight & Thickness Calculator
914 mm
Panel weight
19.7 kg
= 43.4 lb · area 0.66 m²
Capacity (distributed)
49.2 kg
0.74 kPa · factor 0.1
Overhang / desk check
Desk OK
overhang 50 mm / max 150 mm
The weight is the panel mass — what you lift and what the base carries. The capacity is the distributed load the glass itself can carry between supports (or across a full base). For a tempered top on 4-leg stand, recommended thickness for 50 kg distributed: 15 mm. Design stress assumed: 32 MPa tempered.
Six Table Tops, Sized by the Same Model
Each card is the calculator applied to a table people actually buy — the guess that cracks a top and the spec that survives Sunday lunch. Tick what you are sizing to spotlight the matching cards.
Patio table 42" round
1067 mm dia · 12 mm tempered · 3-leg pedestal
26.8 kg
· 39 kg cap
✕ Guess: 10 mm on a 3-leg pedestal — overhang past 150mm, wind lift risk
✓ Spec: 12 mm tempered: overhang 433mm exceeds 150mm — needs a wider pedestal
Optimal build
Office desk 140×70 cm
1400×700 mm · 15 mm tempered · Full base / rim
36.8 kg
· 147 kg cap
✕ Guess: 12 mm floating on 4 legs — forearm lean loads the corners
✓ Spec: 15 mm tempered on full frame: 34 kg, desk point load passes, rigid feel
Coffee table 110×60 cm
1100×600 mm · 10 mm tempered · Full base / rim
16.5 kg
· 71 kg cap
✕ Guess: 8 mm on a lower shelf frame — foot-rest loads crack edges
✓ Spec: 10 mm tempered full base: 16.5 kg, foot-rest safe, no flex
Oval dining 120×80 cm
1200×800 mm · 12 mm lam · Full base / rim
22.6 kg
· 49 kg cap
✕ Guess: 10 mm annealed oval — edge chips from plate setting
✓ Spec: 12 mm laminated: 22 kg, holds if cracked, elegant oval edge
Side table 18" round
457 mm dia · 6 mm tempered · 3-leg pedestal
2.5 kg
· 10 kg cap
✕ Guess: 1/4" annealed on a pedestal — heavy mug tip risk
✓ Spec: 6 mm tempered on 3 legs: 3 kg, 9 kg capacity, stable overhang
Glass Table Top Weight Chart — Round, Rectangular, Oval
Panel mass in kilograms for common table sizes and thicknesses, computed live from the same density model (2500 kg/m³). The number that decides whether one person can lift the top, whether the base is rated for it, and whether tempered is worth the step up from annealed — because the weight is the same either way.
Round tops — weight by diameter
| Diameter | 6 mm | 10 mm | 12 mm | 15 mm |
|---|---|---|---|---|
| 457 mm (18") | 2.5 kg | 4.1 kg | 4.9 kg | 6.2 kg |
| 610 mm (24") | 4.4 kg | 7.3 kg | 8.8 kg | 11.0 kg |
| 762 mm (30") | 6.8 kg | 11.4 kg | 13.7 kg | 17.1 kg |
| 914 mm (36") | 9.8 kg | 16.4 kg | 19.7 kg | 24.6 kg |
| 1067 mm (42") | 13.4 kg | 22.4 kg | 26.8 kg | 33.5 kg |
| 1220 mm (48") | 17.5 kg | 29.2 kg | 35.1 kg | 43.8 kg |
Rectangular tops — weight by size
| Size (mm) | 8 mm | 10 mm | 12 mm | 15 mm |
|---|---|---|---|---|
| 900×500 | 9.0 kg | 11.3 kg | 13.5 kg | 16.9 kg |
| 1100×600 | 13.2 kg | 16.5 kg | 19.8 kg | 24.8 kg |
| 1400×700 | 19.6 kg | 24.5 kg | 29.4 kg | 36.8 kg |
| 1600×800 | 25.6 kg | 32.0 kg | 38.4 kg | 48.0 kg |
| 1800×900 | 32.4 kg | 40.5 kg | 48.6 kg | 60.8 kg |
Reading the chart: a 42-inch (1067 mm) round top steps from 13.4 kg at 6 mm to 33.5 kg at 15 mm — the weight nearly triples while the thickness only increases by 2.5×, because area is constant and the mass scales linearly with thickness. The same logic applies to rectangular tops: a 140×70 cm desk goes from 19.6 kg at 8 mm to 36.8 kg at 15 mm. These are the numbers to check against base ratings and lift plans.
Overhang Rules: Where Pedestal Tables Fail
Overhang is the silent killer of glass table tops — not breakage, not weight, but the top lifting off the base when someone leans at the edge. The rule is simple: max overhang = the smaller of (diameter ÷ 3) or 150 mm. Past that, a 10 kg lean at the rim can pivot the whole top.
📐 3-leg pedestal
Overhang = (diameter − pedestal width) ÷ 2. For a 900 mm top on a 200 mm column, that's 350 mm — well past the 150 mm limit. Widen the column to 600 mm, or shrink the top to 500 mm. This is why narrow pedestal bases pair with small tops only.
🪑 4-leg stand
Overhang = leg inset from edge, usually 50 mm per side. Seldom the limit — the failure mode here is the plate-bending capacity between legs, not tipping. Run the 4-leg numbers in the calculator; capacity drops 70–90% vs full base.
🖼️ Full frame / rim
No overhang limit — the glass sits inside a metal frame or on a solid substrate. Overhang is a frame or substrate question, not a glass one. Thickness becomes a safety and aesthetic choice: 10 mm tempered is plenty for a 1 m top.
The overhang check in the calculator uses a 200 mm pedestal assumption for 3-leg stands — measure your actual pedestal and override mentally. The 150 mm cap is conservative for tempered glass in still air; outdoor tables in wind need half that, which is why patio tables use wide bases or clip the glass down.
Leg Support vs Full Base: The 70% Capacity Drop
The same sheet of 12 mm tempered glass holds 80+ kg on a full metal frame and about 27 kg on a 4-leg stand — the support factor is the single biggest lever in table top sizing. Here's why: a full base means the substrate carries the load and the glass only needs to be strong enough not to crack under local pressure. A 4-leg stand means the glass itself is the spanning structure, bending between corner supports, and the plate-bending capacity collapses.
| 12 mm tempered, 914 mm dia round | Full base | 4-leg stand | 3-leg pedestal |
|---|---|---|---|
| Support factor | 0.30 | 0.10 | 0.08 |
| Distributed capacity | ≈ 80 kg | ≈ 27 kg | ≈ 21 kg |
| Governing limit | Local pressure | Plate bending | Overhang |
| Safe for dining? | Yes | Yes (marginal) | Check overhang |
The implication for purchase orders: if the base is fixed (a specific 4-leg stand, a specific pedestal), the glass thickness is the only free variable, and stepping from 10 mm to 12 mm tempered recovers roughly the capacity lost by going from full base to 4-leg. If the base is not fixed, widening the base — full frame, wider pedestal, or a second support ring — beats any thickness upgrade. The calculator prices both levers in one click.
Tempered Glass Desk Weight Load: The Forearm Lean
Desks are the table top case where people lean — forearms on the edge, 1.0 kN of moment, repeatedly. The desk point-load check in the calculator models exactly this: a 100 kg-equivalent load applied 100 mm from the edge, which is the worst-case stress concentration zone. Annealed fails this check at any sensible thickness; 12 mm tempered on a full frame passes; 15 mm on a 4-leg stand passes.
12 mm on Full frame
34 kg distributed + desk lean passes — the standard office desk build
Desk OK15 mm on 4-leg stand
8 kg distributed + desk lean passes — corner-supported but thick enough
Desk OK10 mm on Full frame
22 kg distributed; desk lean marginal — step to 12 mm for daily use
Step upThe 1.0 kN forearm lean is the industry test load for desk edges — it's not a person sitting on the desk (that's 2.5× higher and needs a different support scheme). For a desk people sit at daily, 15 mm tempered on a full frame is the buy-once choice; 12 mm works for light-use desks and occasional leans.
Three Decisions Behind a Glass Table Top
💡 Tip: size the base before the glass
The support factor (0.30 full, 0.10 4-leg, 0.08 3-leg) is the biggest lever — wider base or full frame beats any thickness upgrade. If the base is already bought, the calculator tells you the minimum tempered thickness for the load; if not, price both levers and pick the cheaper path to the same capacity.
⚠️ Warning: overhang lifts tops in wind
A 900 mm round top on a 200 mm pedestal has 350 mm of overhang — past the 150 mm rule, and a windy patio can lift it off the column entirely. Outdoor tables need either wide pedestals, clips that hold the glass down, or a step to laminated glass (the interlayer adds mass and keeps shards together if it does lift and crack).
❌ Don't: use annealed for any table people touch
Annealed glass breaks into blades, fails the desk point-load check at any sensible thickness, and has no safety rating for horizontal glazing in human use. The 4× strength and safety-dice break pattern of tempered is the baseline, not the upgrade — and laminated tempered is the choice for tops over seating or outdoors, where a cracked pane must not shed pieces.
Glass Table Top FAQ
What the Table Top Model Assumes — and What to Double-Check
The weight model is exact — area × thickness × 2500 kg/m³. The capacity model uses a plate-bending strip with support factors calibrated to corner-supported and full-base cases; for very large tops (over 1.2 m) or unusual support patterns, the real capacity can vary by ±20%. The desk point-load check is a conservative edge-zone model, not a full FEA — for desks carrying heavy equipment, take the printout to a glazing engineer.
The overhang rule (150 mm or diameter ÷ 3) is a stability check, not a stress check — it stops the top lifting off the base under edge load. Outdoor tables in wind need half that, or mechanical clips. For anything above seating areas, specify laminated tempered and read the results against local building codes for horizontal glazing.
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Related: the glass weight calculator runs the pure mass math for any panel — table tops, shelves, doors — while this page adds the support-factor and overhang logic specific to tables. The glass shelf load calculator handles the bracket-supported case (shelves, mantels, ledges), and the shower glass calculator covers door panel weight and hinge matching for frameless bathroom glass.
Order the Table Top Once — at the Right Thickness
Thirty seconds of inputs beats a top that lifts in wind, cracks under a forearm lean, or weighs 20 kg more than the base can carry. Run your shape, try the support styles, and order with the weight, thickness and overhang check printed in one pass.
Back to the table top calculator