Image Resizer - Resize Images Online Free

Last updated March 22, 2026

Tips for Best Results

• Always resize from the original high-resolution source — resizing an already-compressed image degrades quality faster
• Maintain aspect ratio unless you specifically need a different ratio — distorted images look unprofessional
• For square thumbnails, use center crop mode to preserve the most important part of the image
• Resize to the display size — a 1200px image displayed at 400px wastes 3× the bandwidth
• Combine resizing with format conversion (e.g., resize PNG to JPEG) to maximize file size reduction
• For retina/HiDPI displays, generate images at 2× the CSS display size (e.g., 800px image for a 400px slot)

All resizing happens in your browser using the Canvas API. Your images are never uploaded to any server.

Resize to specific dimensions:
  Input:  photo.jpg (4000×3000px, 3.2 MB)
  Output: photo.jpg (1200×900px, 145 KB)
  Settings: Width=1200, Height=900, Maintain aspect ratio=ON

Resize by percentage:
  Input:  banner.png (2400×800px)
  Output: banner.png (1200×400px) — 50% of original
  Settings: Scale=50%

Resize to max width (height auto):
  Input:  portrait.jpg (1080×1920px)
  Output: portrait.jpg (800×1422px)
  Settings: Max width=800, Height=auto (aspect ratio preserved)

Resize to max height (width auto):
  Input:  landscape.jpg (3840×2160px)
  Output: landscape.jpg (1422×800px)
  Settings: Width=auto, Max height=800

Platform-specific resize targets:

Instagram:
  Square post:    1080×1080px
  Portrait post:  1080×1350px
  Landscape post: 1080×566px
  Story/Reel:     1080×1920px

Facebook:
  Profile photo:  180×180px (displays at 170×170)
  Cover photo:    820×312px
  Post image:     1200×630px
  Event cover:    1920×1005px

Twitter/X:
  Profile photo:  400×400px
  Header image:   1500×500px
  In-tweet image: 1200×675px

LinkedIn:
  Profile photo:  400×400px
  Banner:         1584×396px
  Post image:     1200×627px

YouTube:
  Channel art:    2560×1440px
  Thumbnail:      1280×720px

Resizing product images for an e-commerce site:

Requirements:
  - Hero image: 1440×600px
  - Product detail: 800×800px
  - Product thumbnail: 300×300px
  - Cart thumbnail: 80×80px

Workflow:
  1. Upload all product photos (original: ~3000×3000px each)
  2. Set output: 800×800px, quality 85, JPEG
  3. Batch process all images
  4. Download ZIP with all resized images

Before: 25 images × avg 4 MB = 100 MB total
After:  25 images × avg 85 KB = 2.1 MB total
Reduction: 98% — dramatically faster page loads