Transparent Padding

Add transparent or colored padding around your images. Square mode, letterbox mode, with customizable alignment and background color.

Input
Drop an image here or click to browseSupports: PNG, JPG, WEBP, GIF
Output
Result
🛡️Zero server logs. Image padding runs 100% inside your browser via Web Workers. Your files never leave this tab.
🛠️Developer Tool Belt
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Transparent Padding

Transparent Padding adds customizable canvas space around your images. Choose square mode to make images uniform, or letterbox mode to fit into specific dimensions.

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

How to Add Padding to Images

  1. Upload an image by dragging and dropping or clicking to browse.
  2. Choose Square mode for uniform padding or Letterbox for custom dimensions.
  3. Select background color, alignment, and click Add Padding.

Frequently Asked Questions

Questions about image padding? We have answers.

What is Square mode?

Square mode adds padding to make your image square, using the larger dimension as the target size. Perfect for profile photos and thumbnails.

What is Letterbox mode?

Letterbox mode fits your image into a specific canvas size, adding padding as needed. Great for social media and video thumbnails.

Can I use a transparent background?

Yes! Select the transparent option to keep the padding area transparent. Note that JPG output does not support transparency.

Automated E2E Test Suite Logs

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

Stability
100.0%
Passed
11/11
Env
V8-Sandbox
Engine: Vitest RunnerUpdated: 2026/6/13 02:40:10📦 Download Test Datasets
PASSTransparentPaddingTool should render Input and Output labels
PASSTransparentPaddingTool should call processPadding when button is clicked and imageInfo is set
PASSTransparentPaddingTool should disable button when isLoading is true
PASSTransparentPaddingTool should render privacy strip
PASSPure Function Unit Tests should handle valid image input
PASSPure Function Unit Tests should reject invalid input
PASSPure Function Unit Tests should not mutate original input
PASSPure Function Unit Tests should handle boundary input
PASSImage Worker — Padding Action should return success for valid padding action
PASSImage Worker — Padding Action should return error for unknown action
PASSImage Worker — Padding Action should return error for invalid payload
⏱️ 0.18ms📦 1.5KB🎚️ Max Nesting: 3🌿 AST Nodes: 48🛡️ V8 Heap: Healthy
$ codecaven-validator --scope=tool● CLUSTER COMPLIANT

Tool Changelog & Updates

v1.1.02026-06-11
  • Feature: Added comprehensive Vitest test suite covering Tool rendering, worker operations, and shared operation logic — all 871 image tests passing.
  • Fix: Fixed OffscreenCanvas mock patterns in tests for proper constructor instantiation.
v1.0.02026-06-11
  • Feature: Initial release with Square and Letterbox padding modes — 100% client-side via Web Worker.
  • UX: Drag-and-drop upload with before/after preview and customizable alignment controls.
  • UX: Color picker with transparent option for background with 9 alignment presets.
  • Security: Web Worker isolation ensures zero data uploads — all processing stays in the browser.