Image Compression and WebP for Developers

Compress documentation and site images locally, convert PNG/JPEG to WebP, and understand quality, metadata, and browser limits.

Documentation sites, README screenshots, and blog assets often ship as large PNG or JPEG files. You can shrink them locally before commit or deploy—without uploading sources to a third-party compressor.

When WebP helps

WebP usually beats JPEG and PNG on photo-like and UI screenshots at similar visual quality. It is a strong default for web delivery when your CDN or static host serves modern formats.

Use JPEG when you need maximum compatibility in email or legacy pipelines. Keep PNG when you need lossless edges or transparency.

A practical local workflow

  1. Collect the images you want to optimize (docs folder, public/, export from Figma).
  2. Open Image Compressor in the browser.
  3. Drop multiple files, choose WebP or JPEG, and set quality around 0.80–0.85 as a starting point.
  4. Optionally set max width (for example 1280) if full-resolution screenshots are unnecessary.
  5. Click Compress all, compare before/after sizes, and download a zip.

Processing stays on your machine.

Things developers often miss

Metadata — Browser canvas export removes EXIF and ICC profiles. That is usually fine for web assets but not for photography archives.

Transparent PNG → JPEG — Transparency becomes a solid background color. Pick white or your site background deliberately.

PNG “compression” — PNG output in the browser is effectively lossless. Do not expect large savings unless you switch to WebP/JPEG.

Batch limits — Very large images or dozens of files can exhaust mobile browser memory. Compress in smaller batches on phones.

Related tools

Need exact crops first? Use Image Cropper. Preparing App Store assets? Use App Market Image Resizer instead—store sizes are not the same problem as site compression.

Related tools

Use the tools from this article

Image Compressor / WebP Converterimage compressor / compress image online / webp converterImage Cropper / Screenshot Cropperimage cropper / crop image online / crop screenshotMarkdown Preview / Markdown to HTMLmarkdown / markdown preview / markdown to html

Back to articles