画像圧縮

Why compress images online?

Large image files slow down page loading, hurt SEO and make sharing harder. By compressing images online, you can significantly reduce file size for JPG, PNG, WebP and GIF while keeping them visually sharp, which is ideal for websites, blogs, ecommerce product pages and social media posts.

The ImageWA compressor works directly in your browser, so there is no software to install and no hidden upload to third‑party servers. It's a good choice when you need to process sensitive photos or work assets. Batch compression is supported, allowing you to process multiple images at once and download all results in a single ZIP file.

Recommended settings for common use cases

For general web and blog images, a quality level around 75–85% usually gives the best balance between size and visual quality. For ecommerce product photos or portfolio images you can use a slightly higher quality, such as 85–92%, to preserve more detail. For thumbnails, previews or chat stickers, you can lower the quality more aggressively to minimize file size.

When you need to fit under specific upload limits (for example the 8MB Discord limit), you can start with a recommended quality and then use the Max Width / Max Height options to reduce resolution until the file size is small enough. For screenshots or images containing lots of text, it is better to keep a slightly higher quality so that the text remains crisp and easy to read.