Instagram Post Size Checker

What Is the Instagram Post Size Checker?

This tool checks entered pixel dimensions against Instagram's commonly recommended sizes chosen from a dropdown -- Square Post 1080×1080, Portrait Post 1080×1350, or Story/Reel 1080×1920 -- and shows a match or mismatch for the option you selected. There is no landscape option.

How to Use This Tool

Pick the size you are targeting, then enter your image's width and height in pixels. The comparison against that selected size appears instantly.

How the Checker Works

This tool has an image use selector plus width and height boxes. The selector lists three Instagram options: Square Post at 1080 by 1080, Portrait Post at 1080 by 1350, and Story/Reel at 1080 by 1920. You pick the one you plan to publish, type your image's pixel width and height, and the tool tells you whether your dimensions match that selected reference exactly or may be cropped or scaled. It compares against the option you chose rather than automatically guessing the closest one, so switch the selector to test a different format. The page description mentions a landscape option, but the tool itself lists the three above.

Only pixel dimensions are checked. File size, file format, color profile, and video length are not evaluated, and the tool never uploads or opens your image.

Worked Examples (Hypothetical Numbers)

• Select Square Post and enter 1080 by 1080: match.
• Select Portrait Post and enter 1080 by 1350: match. That shape is 4:5, taller than a square, so it takes up more vertical space in a feed.
• Select Portrait Post and enter 4000 by 5000: mismatch, but 4000 divided by 5000 is 0.8, the same 4:5 shape as 1080 by 1350. Scaling it down to 1080 by 1350 preserves the composition.
• Select Square Post and enter 3024 by 4032, a typical phone photo shape: mismatch. The photo is 3:4, so squaring it means cropping the top and bottom.

Step-by-Step Way to Use It

• Decide the format first: a square feed post, a portrait feed post, or a full-screen vertical story or reel cover.
• Read the exact pixel dimensions in your editor or file properties.
• Choose the matching option in the selector and enter width and height.
• If it reports a mismatch, compare shapes by dividing width by height for both your file and the target. Equal ratios mean a simple resize; different ratios mean cropping or extending the canvas.

Common Mistakes

• Forgetting to change the selector. Checking a 1080 by 1350 image against the default square option will report a mismatch even though the file is perfect for a portrait post.
• Assuming a mismatch means the upload will fail. It means the image may be cropped or rescaled, not rejected.
• Cropping a portrait photo into a square without checking faces and text. Reposition the subject before exporting.
• Judging quality only by pixel count. A blurry image at exactly 1080 by 1080 is still blurry.

Choosing Between Formats

A portrait shape fills more of the screen in a scrolling feed, which is why many creators use it for photography and product shots. Squares remain handy for graphics, logos, and content that must look consistent in a grid. Vertical 9:16 suits full-screen story and reel-style content, where you should keep captions and faces away from the top and bottom edges so interface elements do not cover them. Which format is right depends on your subject and layout, not on the tool result.

Interpreting the Result

A match tells you the file is at the reference dimensions. A mismatch tells you the file differs, so plan for the crop or rescale before posting. Since Instagram may change its recommendations, confirm the current guidance in Instagram's own help documentation for anything important, such as a paid campaign.

Frequently Asked Questions