How to compress images for the web without losing visible quality
A practical guide to choosing the right format, size and quality setting so your images load fast and still look sharp.
Updated: 28 October 2026
Large images are the most common reason a web page feels slow. The good news is that most photos can be made several times smaller with no difference you would notice at normal viewing size. This guide walks through the three decisions that matter: dimensions, format and quality.
1. Resize before you compress
A photo from a modern phone is often 4000 pixels wide or more. If the page shows it at 1200 pixels, the browser downloads and then throws away most of those pixels. Resizing first usually saves far more than any quality setting. Use the Image Resizer and choose a width about twice the largest size the image is displayed at on screen if you want it crisp on high-density displays, or the same width if file size matters most.
2. Pick the right format
- Photos: WebP is usually smaller than JPEG at similar visible quality and is supported by all current major browsers. JPEG remains the safest choice for email and older software.
- Screenshots, logos and graphics with flat colours or text: PNG keeps edges sharp. WebP in lossless mode is often smaller still.
- Images that need transparency: PNG or WebP. JPEG has no transparency, so transparent areas become a solid colour.
You can switch formats with the Image Converter (JPG, PNG, WebP).
3. Choose a quality setting
For JPEG and WebP, a quality between 70 and 85 is a sensible starting point for photos. Below about 60 you may start to see blocky areas in skies and smooth gradients. The Image Compressor shows the original and new size side by side, so you can try two or three values and keep the smallest file that still looks good to you.
4. Remove hidden metadata
Photos can carry EXIF metadata such as camera model, date and sometimes GPS location. It adds a few kilobytes and may reveal more than you intend. Check what a file contains with the EXIF Viewer & Metadata Remover. Re-encoding an image in the browser, as the compressor and converter do, does not copy EXIF data into the new file.
A quick checklist
- Resize to the largest size you actually display.
- Use WebP or JPEG for photos, PNG or WebP for graphics.
- Start at quality 80, compare, and adjust.
- Check the result at 100% zoom before publishing.
- Keep the original file in case you need a different size later.
Tools used in this guide
All of these run in your browser: your photos are not uploaded anywhere.