Print sizes look simple — 8×10, 11×14, 16×20 — until you try to buy a frame for a print that's not quite standard, or order a print to fit a frame you already own. The US uses imperial inch sizes for almost all prints and frames. Most US frame retailers stock the standard inch sizes. But corners get cut: cheap frames are sometimes slightly under-size, photographic prints come in their own sizes (4×6, 5×7, 8×10), and European or Etsy prints often arrive in A-series metric sizes that fit no standard US frame at all.
The standard US print sizes
Unlike the European A-series, US sizes don't follow a single mathematical ratio. They're a mix of photographic conventions and historical poster sizes. Most fall into a handful of common dimensions.
| Size (inches) | Millimetres (approx) | Aspect ratio | Typical use |
|---|---|---|---|
| 4×6 | 102 × 152 | 2:3 | Standard photo print |
| 5×7 | 127 × 178 | 5:7 | Photo print, small framed photo |
| 8×10 | 203 × 254 | 4:5 | Most common framed photo size |
| 11×14 | 279 × 356 | 11:14 | Standard wall print size |
| 16×20 | 406 × 508 | 4:5 | Statement wall prints |
| 18×24 | 457 × 610 | 3:4 | Poster prints, large statement |
| 24×36 | 610 × 914 | 2:3 | Large posters, architectural prints |
Frame sizes vs print sizes
This is where confusion starts. A "frame size" usually refers to the size of the opening — the aperture the print sits in. So an "11×14 frame" holds an 11×14 print without a mat, OR it holds a smaller print (e.g. 8×10) with a mat filling the rest of the space.
Always check before buying:
- Print size — the size of the print itself (with no mat).
- Frame opening size — the aperture in the frame. With a mat, this is your mat opening; without, this is your print size.
- Frame outer size — the external dimensions including the moulding. This is what you measure for wall space.
Standard frame sizes with mats
The most common mat combinations in the US:
- 5×7 print in 8×10 frame with a 1.5 inch mat on each side
- 8×10 print in 11×14 frame with a 1.5 inch mat on each side
- 11×14 print in 16×20 frame with a 2.5 inch mat on each side
- 16×20 print in 20×24 frame with a 2 inch mat on each side
These ratios look right because the mat margin grows in proportion with the print. A 1 inch mat on a 16×20 frame looks stingy; the same 1 inch mat on an 8×10 frame looks generous. Always scale the mat to the frame, not by absolute width.
Photo sizes — the odd ones out
Photographic print sizes are the oldest standard in the US sizing system, set by the 35mm film aspect ratio. They don't always play nicely with non-photographic print sizes.
| Photo size | Aspect ratio | Millimetres | Notes |
|---|---|---|---|
| 4×6 | 2:3 | 102 × 152 | Direct from most cameras and phones |
| 5×7 | 5:7 | 127 × 178 | Slight crop from 4×6 ratio |
| 8×10 | 4:5 | 203 × 254 | Significant crop from 2:3 — be aware |
| 11×14 | 11:14 | 279 × 356 | Close to 4:5 but slightly taller |
If you take a photo with your phone (3:2 ratio) and order an 8×10 print, you'll lose roughly 15% from the top and bottom or left and right. Always preview the crop before ordering.
Prints from the UK or Europe
If you've bought a print from a European or Etsy seller, it likely comes in A-series metric sizes:
- A4 (210×297mm) — close to 8×10 but slightly taller and narrower. Will not fit an 8×10 frame.
- A3 (297×420mm) — between 11×14 and 12×16.
- A2 (420×594mm) — close to 16×24.
- A1 (594×841mm) — close to 24×33.
For A-sized prints, you have three options: order a custom-cut mat for a US-size frame, buy an A-sized frame (specialty US frame shops stock these), or have the print re-trimmed to the nearest inch size.
Square and panoramic prints
Square print sizes (10×10, 12×12, 16×16, 20×20 inches) and panoramic sizes (often 24×8, 30×12, 36×12 inches) don't follow the standard ratio set. Frames are widely available but stock less. Always check the exact print dimensions before ordering a frame.
Rule of thumb for buying frames first
If you have a frame and need to choose a print size:
- Measure the inside of the frame opening, not the outside.
- Decide if you want a mat. If yes, the print can be 2–4 inches smaller than the frame on each side.
- Order the print at that smaller size with a custom mat to fill the gap.
Sizing sounds technical but it's geometry. Once the standard inch sizes click, choosing prints and frames stops being guesswork.
A note on frame depth: a thin aluminum picture frame (7.8mm × 25.9mm) sits almost flush with the wall, which makes a real difference on hallway walls and narrow corridors. Deeper wood mouldings sit further out — fine on feature walls, less ideal where you walk past.