How to calculate 4:3 dimensions
- The ratio starts at 4:3. Type a height to get the width, or a width to get the height.
- Check the result in the status line and the preview box, which is drawn at 4:3.
- Look up a standard 4:3 resolution in the table below, or click Copy CSS for aspect-ratio: 4 / 3.
Why use this tool
Presentations for 4:3 projectors
Many classroom and meeting-room projectors are still 4:3, and PowerPoint used 4:3 slides by default until 2013. Size slides, images and charts so they fill the screen without bars at the sides.
iPad layouts and screenshots
Classic iPads use 4:3 screens, from 1024 × 768 on the first models to 2048 × 1536 on the Retina models, and the 12.9-inch iPad Pro is 2732 × 2048, within a hair of 4:3. Plan layouts and mock-ups at the right shape.
Photos from phones and Micro Four Thirds cameras
Phone cameras and Micro Four Thirds cameras shoot 4:3 by default; a 12-megapixel phone photo is 4032 × 3024. Resize for the web or a print layout and keep the original shape.
Retro games and emulators
CRT televisions were 4:3, so classic consoles were made to be shown at that shape, even though many drew on a grid of non-square pixels such as 256 × 224. To scale a 224-line game 4× to 896 lines, use a width of 1195, not the 1024 that square pixels would give.
Private by design
Every calculation runs in this browser tab, so results update the moment you change a value. There is nothing to upload, no account to create and nothing to install.
Good to know
The formula. Width = height × 4 ÷ 3, and height = width × 3 ÷ 4. A slide 600 pixels tall is 600 × 4 ÷ 3 = 800 pixels wide.
Whole pixels. Heights that are multiples of 3, and widths that are multiples of 4, always give whole numbers. Any other value is rounded to the nearest pixel, and the status line shows the exact value it came from: a height of 896 gives a width of 1195, rounded from 1194.6667.
4:3 compared with other ratios. 4:3 is 1.33:1, squarer than the 16:9 (1.78:1) of most screens and videos. A 4:3 picture on a 16:9 screen gets bars at the sides (pillarboxing); a 16:9 picture on a 4:3 screen gets bars at the top and bottom (letterboxing). Photographers also meet 3:2, the shape of 35 mm film and most DSLR sensors, which is wider than 4:3.
Portrait 4:3. Turned upright, 4:3 becomes 3:4. Type 3 and 4 in the ratio boxes for portrait tablet layouts and phone photos held vertically.
Checking a file. Enter a size under Find the ratio of a size to see whether it is exactly 4:3. A size within 1% of 4:3, such as 2732 × 2048 (683:512), is reported as close to 4:3.
In — Ratio 4:3, height typed
600Out — Status line
800 × 600 px · ratio 4:3| Name | Resolution | Megapixels | Typical use |
|---|---|---|---|
| VGA | 640 × 480 | 0.31 | Webcams, early PC games, SD video |
| SVGA | 800 × 600 | 0.48 | Early LCD monitors, small projectors |
| XGA | 1024 × 768 | 0.79 | Projectors, first and second iPad |
| Quad-VGA | 1280 × 960 | 1.23 | Retro game captures at 2× VGA |
| SXGA+ | 1400 × 1050 | 1.47 | Business laptops of the 2000s |
| UXGA | 1600 × 1200 | 1.92 | CRT and early desktop LCD monitors |
| QXGA | 2048 × 1536 | 3.15 | iPad and iPad mini Retina displays |
Frequently asked questions
What is the width of a 4:3 image that is 600 pixels tall?
800 pixels: 600 × 4 ÷ 3 = 800. In the other direction, a 1024-pixel width gives a height of 768.
Should my slides be 4:3 or 16:9?
Match the screen they will be shown on. Most modern TVs, monitors and projectors are 16:9, and PowerPoint, Google Slides and Keynote default to it. Choose 4:3 for older projectors, or when the slides will mostly be viewed or printed on 4:3 devices.
Is 4:3 the same as 1024 × 768?
1024 × 768 (XGA) is one 4:3 resolution. Any size whose width is a third larger than its height is 4:3, from 640 × 480 to 2048 × 1536 and beyond.
How do I show a 4:3 video on a 16:9 screen?
Either keep the whole picture with bars at the sides, or crop the top and bottom to fill the screen. On a 1920 × 1080 screen, the uncropped 4:3 picture is 1440 × 1080 and leaves 240 pixels of bars on each side.
Why do retro games look stretched or squashed?
Many consoles drew images on a grid such as 256 × 224 that the CRT stretched to fill a 4:3 screen, so their pixels were not square. Scaled by whole multiples on a modern screen, they look too narrow. Calculating the 4:3 width for your target height restores the original shape.