How to Calculate the Outside Dimensions of a Picture Frame

Do you need to work out the total outside dimensions for a picture frame before you buy it? We've put together this helpful guide so you can easily calculate these dimensions, when you cannot physically measure the frame.  

What Are the Different Dimensions of a Picture Frame?

There are two dimensions that could be important for when you are looking to buy a picture frame or photo frame:

  • Internal Frame Dimensions: What size artwork can the picture frame hold? Sometimes this is referred to as the “glass size”.
  • Outside (External) Frame Dimensions: What size or space will it take up on the wall?

When buying Picture frames and photo frames in retail stores or online, the internal frame dimensions are commonly displayed and used to specify the picture frame.

If your picture frame options also include a matboard border, then the “glass size” internal frame dimensions will still be applicable.  


Measuring a picture frame with a tape measure


But What if I Need the Outside Dimensions of the Frame?

Sometimes you may need to calculate the overall external dimensions of a picture frame. For example, if you have a particular space you need to fill on a wall, or other possible sizing constraints for display.  If you cannot physically measure this with a tape measure, then you will need to know some extra information about the picture frame, so you can work this out:

  • The width of the frame moulding – This is how wide the picture frame measures across the top face.
  • The overlap of the lip of the picture frame - You also need to allow for overlap of the lip of the frame as well, which is approximately +/-0.5cm on each side. In most cases, 1.0cm in total. Note that this is approximate, as you need to allow some slight space and movement to fit the glass and backing into the frame. This can commonly vary by 0.2-0.3cm.

The overall external (outside) dimension of a picture frame can be calculated as follows:

  • Plus the internal frame/artwork dimensions
  • Plus the width of the frame moulding on both sides
  • Minus the width of the frame lip overlap on both

Please see the diagram below to help explain some of the measurements.



Example: What are the External Dimensions for an 8x10 Elegant Black Photo Frame?

Below is an example of our popular 8x10in Elegant Black Photo Frame. The internal dimensions of this frame are 8x10 inches, or exactly 20.3 x 25.4cm. We know that the frame moulding with is 2cm wide and the overlap for the glass lip with be approximately 0.5cm.

The overall dimensions would be calculated as follows:

Overall Frame Width = 

  • Internal frame/artwork width dimension = 20.3cm
  • Plus Frame Moulding Width – Frame Lip Overlap = 2cm – 0.5cm = 1.5cm
  • Plus Frame Moulding Width – Frame Lip Overlap = 2cm – 0.5cm = 1.5cm
  • Total Outside Width Dimension = approximately 23.3cm

Overall Frame Height = 

  • Internal frame/artwork height dimension = 25.4cm
  • Plus Frame Moulding Width – Frame Lip Overlap = 2cm – 0.5cm = 1.5cm
  • Plus Frame Moulding Width – Frame Lip Overlap = 2cm – 0.5cm = 1.5cm
  • Total Outside Height Dimension = approximately 28.3cm

Please see the diagram below to help explain this example:


What are the Widths of All of Your Timber Picture Frame Mouldings?

Below is an alphabetical reference listing which provides the frame moulding width for each of our popular styles of timber picture frames:

Please note that these dimensions above also include the lip overlap, which you would need to subtract (0.5cm).

We hope this information can help you with understanding how to measure the outside dimensions for a picture frame. However, if you need any further help or assistance, please contact us and we will always be happy to help!

Picture Frame Size Conversion Table and Reference Chart

We've also created a helpful conversion chart of common standard Australian picture frame sizes which includes a conversion table and visual diagrams so you can see what's easy to find and what the measurements will be in either centimeters or inches. 
Frame Sizes Reference Chart

Shop Australia's Largest Range of Photo Frames Online with Profile

Explore the complete range of Picture & Photo Frames from Profile Australia. Whether you're looking for black frames, timber frames, natural oak frames, metal frames or even specialty frames like panoramic frames, we offer a full range of picture framing solutions in all types of shapes, styles and sizes. 

All proudly made in Australia with eco-sustainable timbers and a lifetime guarantee! 

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