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Shaishav Patel
Shaishav Patel

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Image Size Requirements for Every Platform — And How to Resize in One Step, Free

Every platform has its own image size rules, and ignoring them costs you quality. Instagram crops your post. LinkedIn stretches your banner. Your email client shows a blurry header.

The fix is always the same: resize the image to the exact pixel dimensions before uploading.

Resize any image to exact dimensions: Image Resizer — Pixels, Aspect Ratio, No Upload


Standard Dimensions by Platform

Social Media

Platform Use Recommended Size
Instagram Square post 1080 × 1080px
Instagram Portrait post 1080 × 1350px
Instagram Story / Reel 1080 × 1920px
Instagram Profile photo 320 × 320px
LinkedIn Banner / cover 1584 × 396px
LinkedIn Post image 1200 × 627px
LinkedIn Profile photo 400 × 400px
Twitter / X Header 1500 × 500px
Twitter / X Post image 1200 × 675px
Facebook Cover photo 851 × 315px
Facebook Post image 1200 × 630px
YouTube Channel art 2560 × 1440px
YouTube Thumbnail 1280 × 720px

Email

Use Recommended Size
Email header banner 600px wide (height varies)
Email inline image 480–600px wide
Email signature logo 200–300px wide

Email clients display images at 600px wide on desktop. Anything wider gets scaled down, wasting file size and potentially causing layout issues on mobile.

Website and Blog

Use Recommended Size
Blog cover image 1200 × 630px
Open Graph / OG image 1200 × 630px
Favicon 32 × 32px, 180 × 180px
Hero section background 1920 × 1080px

How to Resize to Exact Dimensions

  1. Go to the Image Resizer
  2. Upload your image (JPG, PNG, WEBP supported)
  3. Enter the width and height in pixels from the table above
  4. Choose whether to lock aspect ratio (prevents stretching) or set both dimensions exactly
  5. Click Resize and download

The tool runs entirely in your browser — your image is never uploaded to a server.


Aspect Ratio Lock vs Exact Dimensions

Lock aspect ratio keeps the image proportions intact. If you resize a 4000×3000px photo to 1200px wide with ratio locked, it becomes 1200×900px — same proportions, smaller size. Use this for most cases.

Exact dimensions forces the image to fit the specified width and height regardless of original proportions. This can cause stretching if your image's aspect ratio doesn't match the target. Use this only when the platform strictly requires both dimensions (like Instagram's 1080×1080 square, where you'd want to crop first, then resize).

For platforms with strict aspect ratios (Instagram square, LinkedIn banner), crop the image to the right ratio first using the Image Crop tool, then resize to exact pixels.


Retina / High-DPI Displays

Many modern devices have 2× or 3× pixel density screens (Retina on Apple, OLED on Android flagships). For web images displayed on these screens, export at 2× the CSS display size:

  • If your image displays at 600px wide, export at 1200px wide
  • The browser scales it down, and it appears sharp on retina screens

For social media, the platform handles this — stick to the recommended dimensions.


File Size After Resizing

Smaller pixel dimensions = smaller file size, but not always enough. For web and email, also compress the image after resizing. A 1200×630px PNG can still be 2MB+ without compression — which affects page load speed and email deliverability.

The common workflow: resize → compress → upload.


Related Tools

  • Image Crop — crop to aspect ratio before resizing to avoid distortion
  • Image Compressor — reduce file size after resizing without visible quality loss
  • Image Converter — convert between JPG, PNG, and WEBP after resizing

Resize your image to exact platform dimensions: Image Resizer at Ultimate Tools — free, no upload, instant download.

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