Aspect Ratios: Chart of Common Ratios, Resolutions and Calculator

Common aspect ratios chart

A ratio is a shape, not a size. A phone screen and a cinema screen can both be 16:9. The decimal column (width ÷ height) is the easiest way to compare ratios written with different numbers.

Portrait shapes reverse the numbers: 9:16 (0.56) for TikTok, Reels, Shorts and Stories; 4:5 (0.80) for portrait feed posts; 2:3 (0.67) for upright camera photos and Pinterest pins; 3:4 (0.75) for upright phone photos.

2.39:1 cinema scope16:9 TVs, monitors, video3:2 camera photos4:3 older TVs, phone photos

Aspect ratio calculator

Enter a resolution or any width and height (pixels, inches, cm) to get its simplified ratio. The second tool scales a ratio to a new size or works out the width and height of a screen from its diagonal.

How to calculate an aspect ratio

1. Divide width by height for the decimal form. 1920 ÷ 1080 = 1.78, written 1.78:1. Film ratios are usually given this way.
2. Reduce to whole numbers by dividing both sides by their greatest common divisor. For 1920 × 1080 the divisor is 120, which gives 16:9. For 3440 × 1440 it is 80, giving 43:18, which is marketed as 21:9.
3. Find a missing dimension by cross-multiplying. Height = width × (ratio height ÷ ratio width). A 1280-pixel-wide 16:9 video is 1280 × 9 ÷ 16 = 720 pixels tall.
4. Get width and height from a diagonal with Pythagoras. For a ratio a:b, width = diagonal × a ÷ √(a² + b²) and height = diagonal × b ÷ √(a² + b²). For 16:9 that is width = 0.872 × diagonal and height = 0.490 × diagonal.

Some resolutions do not reduce neatly. 1366 × 768, common on older laptops, reduces to 683:384 (1.779:1), which is 16:9 to within 0.1% and is always treated as 16:9. 2560 × 1080 reduces to 64:27 (2.37:1) and is sold as 21:9.

Screen resolutions by aspect ratio

"4K" on a TV or monitor means 3840 × 2160, exactly four times 1920 × 1080. Cinema 4K (DCI) is 4096 × 2160, a slightly wider 1.90:1 container. Monitor sizes for each ratio are in the monitor size chart.

TV and film aspect ratios

Every TV sold today is 16:9, defined for HDTV in ITU-R BT.709 and kept for 4K and 8K in BT.2020. Films are made in other shapes, which is why black bars appear.

• 4:3 (1.33:1) and Academy (1.375:1): the shape of early film and of standard-definition television until the 2000s.
• 16:9 (1.78:1): chosen in the 1980s as a compromise. It sits close to the geometric mean of 4:3 and 2.35:1, so both fit on it with similar-sized bars.
• 14:9 (1.56:1): a broadcast compromise used in the UK during the switch to widescreen, cropping 16:9 pictures slightly so they would also look acceptable on 4:3 sets.
• 1.85:1 "flat": the standard widescreen cinema format in the US. On a 16:9 TV it leaves thin bars, about 2% of the screen height at the top and bottom.
• 2.39:1 "scope": anamorphic widescreen. Older films and many people still call it 2.35:1, the figure used before a 1970 projection-standard change; you will also see 2.40:1.
• IMAX: 1.43:1 on 70 mm film and 1.90:1 in digital IMAX theaters. Films that switch to IMAX scenes change shape on a TV.

Zoom or "fill" modes remove the bars by cropping the sides of the picture or stretching it. For other TV sizes see the TV size guide.

Aspect ratios of phones, tablets and laptops

• Phones: around 19.5:9 (iPhones and many Samsung models, about 2.17:1) or 20:9 (many Android phones, 2.22:1). Upright, these are tall and narrow, which is why 9:16 video fills most of the screen with small bars. The phone screen size guide lists dimensions.
• Tablets: Android tablets are mostly 16:10 (for example 2560 × 1600). iPads vary: the larger iPad Air and iPad Pro models are 4:3 (2732 × 2048 and 2752 × 2064), the 11-inch models about 1.44:1 (2360 × 1640 and 2420 × 1668), and the iPad mini about 1.52:1. A 4:3 tablet suits documents and comics; 16:10 suits video.
• Laptops: 16:9 was standard through the 2010s; 16:10 is now common on Windows laptops. Microsoft Surface models use 3:2, and MacBook Air and Pro screens are about 1.54:1 (for example 2560 × 1664), between 3:2 and 16:10.
• Monitors: 16:9 for most, 16:10 for some office models, 21:9 and 32:9 for ultrawides.

The "native" aspect ratio of a display is the shape of its physical panel. Setting a resolution of a different ratio (for example 1024 × 768 on a 16:9 laptop) either stretches the image or adds black bars.

Photo and print aspect ratios

Cameras and phones capture in one ratio, and print sizes come in several others, so prints usually require some cropping.

To print without losing anything, choose a print size with the same ratio as the photo, or ask for a border. Frame sizes are covered in the picture frame size guide and standard photo sizes in the photo print size chart.

Setting an aspect ratio in software and on cameras

• Web pages (CSS): aspect-ratio: 16 / 9; on an element keeps that shape at any width. Embedded videos and image placeholders use it to stop the page jumping while media loads.
• Image editors: the crop tool in Photoshop, Lightroom, GIMP and phone photo apps accepts a fixed ratio (for example 4 × 5 or 16:9). Crop to the ratio first, then resize to the pixel size you need.
• Video editors: the project or sequence settings fix the frame (1920 × 1080 for 16:9, 1080 × 1920 for 9:16). Footage of another shape is either letterboxed or scaled to fill and cropped.
• Phone cameras: most phone sensors are 4:3. Choosing 16:9 or 1:1 in the camera app crops the sensor image, so you capture fewer pixels than in 4:3 mode. Shoot in 4:3 if you are not sure, and crop later.
• Displays: set the resolution that matches the panel's native ratio. Most screens offer an "aspect" or "scaling" option to show other shapes with bars instead of stretching them.

Which aspect ratio to choose

• Video for YouTube, TV or a monitor: 16:9, at 1920 × 1080 or 3840 × 2160.
• Short vertical video (TikTok, Reels, Shorts, Stories): 9:16 at 1080 × 1920.
• Feed posts: 1:1 (1080 × 1080) or a portrait 4:5 (1080 × 1350) to take more screen space. Current sizes for each platform are in the social media image size guide.
• Photos for printing: shoot in 3:2 for 4 × 6 and poster sizes, or 4:3 if most prints will be 18 × 24 or similar.
• Presentations: 16:9, matching projectors and screens; 4:3 only for old projectors.
• Film look: 2.39:1 or 1.85:1, usually by adding bars inside a 16:9 or 4K frame (3840 × 1607 picture area for 2.39:1).

Frequently asked questions