Picture Frame Molding Calculator
Buying the right amount of picture frame molding before you start cutting saves money and trips to the supplier. A rectangular frame requires four pieces of molding mitre-cut at 45 degrees: two horizontal pieces matching the outer width and two vertical pieces matching the outer height. The total linear length needed is therefore 2 times the sum of the outer width and outer height. Because each mitre cut removes a small amount of material, and because real-world cutting always produces some waste from re-cuts and off-cuts, professional framers add 10% to their calculated total. Molding is typically sold in 8-foot or 10-foot sticks, so you also need to know how many sticks to purchase. This calculator takes your frame outer width, outer height, and the number of frames you are making, then returns the molding needed per frame, the total for all frames, the total with 10% waste, the length in linear feet, and the number of standard 8-foot or 10-foot sticks required.
Per frame: -- in | Total (all frames): -- in | With waste: -- in | Linear feet: -- ft
How it is calculated
molding_per_frame = 2 x (outer_width + outer_height)
total_molding = molding_per_frame x number_of_frames
with_waste = total_molding x 1.10
linear_feet = with_waste / 12
sticks_8ft = ceil(with_waste / 96)
sticks_10ft = ceil(with_waste / 120)
Worked example
- Frame outer dimensions: 12 x 16 inches. Making 2 frames.
- Molding per frame: 2 x (12 + 16) = 2 x 28 = 56 inches.
- Total for 2 frames: 56 x 2 = 112 inches.
- With 10% waste: 112 x 1.10 = 123.2 inches.
- Linear feet: 123.2 / 12 = 10.27 feet.
- 8-foot sticks (96 in each): ceil(123.2 / 96) = 2 sticks.
- 10-foot sticks (120 in each): ceil(123.2 / 120) = 2 sticks.
Molding length reference by frame size
| Frame size (outer) | Per frame (in) | With 10% waste (in) | Linear feet | 8-ft sticks |
|---|---|---|---|---|
| 5 x 7 in | 24 | 26.4 | 2.20 | 1 |
| 8 x 10 in | 36 | 39.6 | 3.30 | 1 |
| 11 x 14 in | 50 | 55.0 | 4.58 | 1 |
| 12 x 16 in | 56 | 61.6 | 5.13 | 1 |
| 16 x 20 in | 72 | 79.2 | 6.60 | 1 |
| 18 x 24 in | 84 | 92.4 | 7.70 | 1 |
| 20 x 24 in | 88 | 96.8 | 8.07 | 2 |
| 24 x 30 in | 108 | 118.8 | 9.90 | 2 |
| 24 x 36 in | 120 | 132.0 | 11.00 | 2 |
Frequently asked questions
How do I calculate how much molding I need for a picture frame?
A rectangular picture frame requires four pieces of molding: two horizontal pieces equal to the outer width and two vertical pieces equal to the outer height. Each piece is mitre-cut at 45 degrees at both ends. Total molding = 2 x (outer width + outer height). Add 10% for waste from mitre cuts and any measurement errors.
Why is 10% added for waste?
Mitre-cutting frame molding at 45-degree angles wastes a small amount of material at each cut. There are eight cuts per frame (two per piece, four pieces). Additional waste accounts for measurement errors, re-cuts, and any defects in the molding. Professional framers typically add 10% to 15% waste allowance.
What are standard molding stick lengths?
Picture frame molding is typically sold in 8-foot (96-inch) or 10-foot (120-inch) lengths. Some suppliers also offer 12-foot lengths. When calculating how many sticks to buy, divide your total molding needed (with waste) by the stick length and round up to the nearest whole number.
Should I use frame outer or inner dimensions?
This calculator uses frame outer dimensions, which are the total outside dimensions of the finished frame. Frame inner dimensions (the rabbet opening where the mat and artwork sit) are typically smaller than the outer dimensions by twice the molding width. If you only know the inner dimensions, add twice your molding profile width to each dimension to get the outer measurement.
Can I calculate molding for multiple frames at once?
Yes. Enter the number of frames in the quantity field and the calculator multiplies the per-frame molding requirement by that number. This is useful when making a batch of matching frames. Note that buying molding for multiple frames at once may allow you to use off-cuts from one frame on another, reducing actual waste below the 10% estimate.
Official sources
- Professional Picture Framers Association: ppfa.com - framing industry standards and training resources.
- Molding length calculations are based on standard industry practice for mitre-cut rectangular frames as documented by professional framing associations.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.