Aspect Ratio Guide for Instagram and WhatsApp AI Photos

What aspect ratio means

Aspect ratio is the shape of an image written as width to height. A 1:1 image is square. A 4:5 image is a little taller than it is wide. A 9:16 image is tall and narrow, the shape of a phone screen held upright. A 16:9 image is wide, like a YouTube video or a TV.

Ratio and pixel size are related but not the same. A 4:5 image can be 1080 by 1350 pixels or 2160 by 2700 pixels; both have the same shape. Midjourney's documentation makes the same point: aspect ratio is not the same as image dimensions. When you prompt an AI app, the ratio matters most, because the shape decides what fits in the frame. You can resize later if needed.

Quick reference table

Our prompt generator has these ratios built in. Pick 4:5, 9:16, 1:1, 3:4 or 16:9 and it adds the right line to your prompt.

Instagram posts: what the help page says

Instagram's help page on image resolution says it uploads photos at the best quality it can, up to a width of 1080 pixels. When a photo is between 320 and 1080 pixels wide, Instagram keeps the original resolution as long as the aspect ratio is between 1.91:1 and 3:4, which the page describes as a width of 1080 pixels with a height between 566 and 1440 pixels.

The same page explains what happens outside those limits. If the ratio is not supported, the photo is cropped to fit a supported ratio. A smaller photo is enlarged to 320 pixels wide, and a larger one is sized down to 1080 pixels wide. To keep the full 1080 pixel width, Instagram suggests uploading a photo at least 1080 pixels wide with a ratio between 1.91:1 and 3:4.

For a portrait of yourself, 4:5 is a safe, popular choice. It sits comfortably inside the supported range and gives more height than a square, which suits half-body and full-body shots like saree or wedding looks. If you want the tallest shape Instagram supports for photos, ask for 3:4.

Reels, stories and WhatsApp status

Instagram's reels help page says you can upload a reel with an aspect ratio between 1.91:1 and 9:16, and that reels should have a minimum frame rate of 30 FPS and a minimum resolution of 720 pixels. It gives the recommended cover photo size as 420 by 654 pixels, a 1:1.55 ratio. If you are making an AI image to use in a reel, 9:16 fills the screen.

For stories, Meta's business help page on Instagram Stories ads describes the fullscreen vertical format and recommends a 9:16 ratio at 1080 by 1920 pixels, with a minimum of 600 by 1067. That page is written for ads, but it describes the same fullscreen vertical screen your own story uses. It is sensible to keep your face and any text away from the very top and bottom edges, where app buttons and labels can sit on top of the picture.

WhatsApp's status page says status updates can hold photos, videos, voice notes and text, and disappear after 24 hours. We did not find an official pixel size for status photos, so we suggest 9:16 because it matches an upright phone screen. WhatsApp's help page also notes that status media is usually compressed and may look lower quality than the original, so start from a sharp image.

How to ask an AI app for the right shape

1. Decide where the photo will go before you write the prompt.
2. Add the ratio at the end of your prompt, for example "Vertical 4:5 aspect ratio" or "Tall 9:16 aspect ratio for a phone screen".
3. Add a framing note so the crop does not cut you: "keep my full head and hair in frame with some space above".
4. In ChatGPT, you can also use the aspect ratio picker; OpenAI's help page says the editor can regenerate an image in a different aspect ratio.
5. In Midjourney, add --ar followed by the ratio at the end of the prompt. Its docs say the default is 1:1 and the ratio cannot contain decimals, so write 191:100 rather than 1.91:1.
6. Check the result before posting. If the shape is wrong, ask again with the ratio stated first.

Changing the ratio after the image is made usually means regenerating or cropping, and cropping can cut off hands, feet or your head. It is better to ask for the right shape from the start. More fixes are in our common AI photo problems guide.

Profile photos and DPs

For an Instagram profile photo or WhatsApp DP, ask for a 1:1 square with your face centred and a little space around your head. The picture appears very small in lists and chats, so a close-up from the shoulders up reads better than a full-body shot. A plain or softly blurred background helps your face stand out. Our Instagram DP prompts and professional headshot prompts are written for this square, face-first layout.