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Aspect ratio calculator

Type a width and a height, or pick a common size. See the ratio, the closest standard shape and how it fits each platform.

This aspect ratio calculator turns any width and height into a simple ratio like 16:9 or 9:16. Type your size or pick a preset to see the ratio, its decimal, the closest standard shape and the size to use on TikTok, Reels, Shorts and YouTube. It runs in your browser and costs nothing.

Enter a size

Width (px)Height (px)

Or pick a common size

Aspect ratio

9:16

Decimal 0.5625 · Portrait (vertical) · Exactly 9:16 (TikTok, Instagram Reels, YouTube Shorts, Stories)

Resize 1080 x 1920 for each platform: the biggest copy of your shape that fits the platform size.
Where (ratio, size)	Your shape fits at	Result
TikTok, Reels and Shorts9:16 · 1080 x 1920	1080 x 1920	Fills it
YouTube and widescreen16:9 · 1920 x 1080	608 x 1080	Bars or crop
Square feed post1:1 · 1080 x 1080	608 x 1080	Bars or crop
Instagram portrait post4:5 · 1080 x 1350	760 x 1350	Bars or crop
Classic 4:34:3 · 1440 x 1080	608 x 1080	Bars or crop
Ultra wide 21:921:9 · 2520 x 1080	608 x 1080	Bars or crop

New width (px)

Same shape at that width

Type a new width

Make a 9:16 video

What is an aspect ratio?

An aspect ratio is the shape of a picture or video: its width compared with its height. 16:9 means 16 units wide for every 9 units tall. It says nothing about sharpness; 1280 x 720 and 3840 x 2160 are both 16:9.

Tall shapes like 9:16 fill a phone held upright. Wide shapes like 16:9 fill a laptop, a TV or a phone turned on its side. Square 1:1 sits in between.

Which aspect ratio should I use for each platform?

TikTok recommends vertical 9:16 video and also accepts 16:9 and 1:1 (see the TikTok video size page for the sources). Instagram Reels take any shape from 1.91:1 to 9:16, and 9:16 fills the screen (Instagram Reels size). YouTube Shorts are square or vertical. Regular YouTube videos are 16:9.

If you post one video everywhere, make it 9:16 and keep words away from the edges: see the TikTok safe zone for where the buttons and caption sit.

How do I use this video aspect ratio calculator?

Type the width and height of your video or picture in pixels, or press one of the common sizes. The ratio updates as you type. The table shows how your shape fits each platform size, and the new width box gives the matching height so the shape stays the same.

To see what the video itself will cost to make, use the AI video cost calculator.

Make the video in the studio

Turn an idea into a finished video in the Reviral studio. It makes 9:16, 16:9 and 1:1 videos; this button opens it with 9:16 picked.

Make a 9:16 video

Aspect ratio questions

How do I work out an aspect ratio?

Divide the width and the height by the biggest number that divides both. 1920 and 1080 both divide by 120, which gives 16 and 9, so the ratio is 16:9. The calculator does this for you and also shows the ratio as one decimal number.

What is the aspect ratio of 1080 x 1920?

1080 x 1920 is 9:16. It is a tall, vertical shape: the height is 16/9 of the width. It is the full-screen size used for TikTok, Instagram Reels, YouTube Shorts and Stories.

What aspect ratio is a YouTube Short?

YouTube counts a video as a Short when it is square or vertical and up to three minutes long, so 9:16 and 1:1 both work. 9:16 fills a phone screen; 1:1 leaves space above and below.

What does the resize table show?

For each platform size it shows the biggest copy of your shape that fits inside it. If your shape matches the platform, it fills the frame. If not, the video gets bars at the sides or top, or you crop it to the platform shape.

Which shapes can the Reviral studio make?

The studio makes 9:16, 16:9 and 1:1 videos. When your size is exactly one of those, the button below the result opens the studio with that shape already picked.