onul.works

Image Compressor

Reduce image file size with browser-side compression and compare quality before downloading.

◴ No data stored ⌁ Free

Concept

Image compression is balancing size, quality, and format compatibility

Use this tool to lower image file size for web uploads, blogs, and product pages while keeping visual quality at an acceptable level.

In upload-heavy workflows like CMS posts, storefront product pages, and shared docs, compression is used to reduce failures and improve load time by preparing a lighter image first.

Keep the original file, create a compressed candidate, and compare previews before downloading so readability and edges remain acceptable for the target screen.

Format scenario

Use JPEG for photos, WebP for efficient web delivery, and PNG when transparency or exact edges are required.

Quality trade-off

Lower quality increases compression ratio but can cause blur and banding; choose a quality value that matches each use case (blog hero, thumbnail, product card).

Visual check before publish

Before applying, verify the preview on desktop and mobile for artifacts, color shifts, and readability to match real page rendering.

This tool focuses on image-size reduction. Keep originals separately, and verify post-compression output in the actual target page to confirm shipping quality.

Image input
Compression result
Compression result details will appear here.

How to use

  1. 1 Upload the image you want to compress and adjust the quality value.
  2. 2 Choose the output format: original, WebP, AVIF, JPEG, or PNG.
  3. 3 Run compression, compare the size change, and download the result.

Common use cases

  • Reduce image file size
  • WebP, AVIF, and JPEG conversion
  • Quality-adjusted image download

Frequently asked questions

Which output formats can I compress to?

You can choose keep original, WebP, AVIF, JPEG, or PNG output and adjust quality from 10 to 100.

How can I review and save the compressed result?

After compression, you can check the result preview, file size, and size change, then save it with the download button.

Where is the image processed?

Browser processing re-saves the image with canvas without upload. Only server optimization sends it to Cloud Run for libvips-based processing.

Related workflow

Image CompressorCompress the page image first so later conversion or icon work starts from a lighter file. → Base64 to ImageIf there is a Base64 version, open it as an image and compare it with the source. → Favicon GeneratorThen check whether the compressed primary image can also work as a site icon.