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[tool] ·

Image Compression / WebP Conversion

Compress JPEG/PNG to WebP in the browser, up to 20MB per file. Everything stays local.

stack: canvas, webp, vanilla-js

Compress before the CDN, save the money.

What it is

Writing Notes usually means pasting screenshots. Raw files are often several MB; throwing them at the CDN is slow and expensive.

This tool re-encodes JPEG / PNG as WebP entirely in the browser, with an adjustable quality slider. Pure local processing—the image never goes to a server.

How to use

  1. Drop the image in
  2. Adjust the quality slider (default 80)
  3. Download the result

Limits

  • Per-file ≤ 20MB (browser memory limits)
  • Output is WebP (Safari 14+ / all Chrome versions)
  • No AVIF (yet)

What we use it for

  • Compressing screenshots in our Notes
  • Shrinking customer-support email attachments
  • Batch-converting product photos to WebP before pushing them to the CDN

Tech details

  • Uses <canvas>’s toBlob('image/webp', quality)
  • Large files chunked with createImageBitmap
  • No npm packages