Image Resizer

Resize images by width, height, percentage, or exact dimensions while maintaining aspect ratio. 100% client-side with zero data upload.

Width:px
Drop images here or click to browseSupports: PNG, JPEG, WEBP, AVIF
🛡️Zero server logs. Image resizing runs 100% inside your browser. Your files never leave this tab.
🛠️Developer Tool Belt
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Image Resizer

Image Resizer is a 100% browser-based tool for resizing images. All processing happens locally via Web Workers — your images never leave your device.

🔒 Client-side only⚡ Web Worker processing🌐 Works offline🛡️ Zero server logs

How to Resize Images Online

  1. Drag and drop an image or click to select from your device.
  2. Choose a resize mode: by width, height, percentage, or exact dimensions.
  3. Enter your desired values and click Resize to get your result.

Frequently Asked Questions

Got questions about image resizing? We've got answers.

Will resizing affect image quality?

Resizing to smaller dimensions may reduce sharpness slightly. Enlarging beyond original size will reduce quality as the image is interpolated.

What does 'Maintain Aspect Ratio' do?

When enabled, changing one dimension automatically adjusts the other to keep the image proportions the same, preventing distortion.

Is Image Resizer safe to use?

Yes, absolutely. All processing happens entirely in your browser via Web Workers. Your images are never uploaded to any server.

Automated E2E Test Suite Logs

Our build systems validate edge-case processing under extreme conditions before each deployment.

Stability
100.0%
Passed
9/9
Env
V8-Sandbox
Engine: Vitest RunnerUpdated: 2026/6/13 02:40:10
PASSResize Operation should be async function
PASSResize Operation should throw on invalid image
PASSResize Operation should throw on unknown mode
PASSImageResizerTool renders dropzone
PASSImageResizerTool renders Resize button
PASSImageResizerTool renders privacy strip
PASSImageResizerTool has multiple file input
PASSImage Resizer Worker should handle resize action
PASSImage Resizer Worker should handle unknown action
⏱️ 0.18ms📦 1.5KB🎚️ Max Nesting: 3🌿 AST Nodes: 48🛡️ V8 Heap: Healthy
$ codecaven-validator --scope=tool● CLUSTER COMPLIANT

Tool Changelog & Updates

v1.1.02026-06-12
  • Fix: Fixed resize operation crashing due to non-transferable Blob in postMessage.
  • Feature: Batch resize with width, height, percentage, and exact modes — supports maintain-aspect-ratio.
  • UX: Card-based UI with thumbnails, before/after dimensions, and size change percentage.
v1.0.02026-06-11
  • Feature: Initial release with four resize modes: width, height, percentage, and exact dimensions — 100% client-side via Web Worker.
  • UX: Aspect ratio lock toggle with automatic dimension calculation.
  • UX: Real-time preview overlay showing the resized area within the original image.
  • Security: Web Worker isolation ensures zero data uploads.