How to Compress Images for Your Website Without Losing Quality

Published 2026-10-24

Images are usually the heaviest thing on a web page. A single photo straight from a phone can be 4 or 5 MB, which is more than many entire well-built pages. Shrinking images is one of the quickest ways to make a site faster, and done properly, visitors cannot see the difference.

Step 1: resize to the size you actually display

A modern phone camera produces images around 4000 pixels wide. Most blog content areas are 700 to 1200 pixels wide. Uploading the full camera image means the visitor downloads millions of pixels that are thrown away when the browser scales the picture down.

A good rule is to export images at about twice the width they appear on screen, so they stay crisp on high-resolution displays. For a 800-pixel content column, 1600 pixels wide is plenty. Resizing alone often cuts the file size by 70% or more.

Step 2: choose the right format

  • JPG is the classic choice for photographs. It compresses smooth color gradients very well.
  • WebP does the same job as JPG but usually produces files around a quarter to a third smaller at similar visual quality. Every current major browser supports it, so it is the best default for photos on the web today.
  • PNG is lossless and supports transparency. Use it for logos, icons and screenshots with sharp text, not for photos, where it creates very large files.
  • SVG is the best option for simple logos and icons, because it is vector-based and stays sharp at any size.

Step 3: pick a sensible quality setting

JPG and WebP let you choose a quality level. The relationship between quality and file size is not linear. Dropping from 100% to around 80% can halve the size with no visible change, while going below about 60% starts to introduce blocky artifacts around edges and in skies.

Try 75% as a starting point, then compare the result with the original at actual size. If you cannot spot a difference, try going a little lower. Our image compressor shows the new file size and a preview as you move the slider, all inside your browser.

Step 4: strip metadata

Photos carry hidden EXIF data such as camera model, settings and sometimes GPS location. It adds a few kilobytes and can reveal where a photo was taken. Re-saving the image through a compressor that draws it onto a canvas, as ours does, removes this data automatically.

Step 5: let the browser help

Once images are compressed, a couple of HTML attributes help them load efficiently:

  • Add loading="lazy" to images further down the page so they load only when the visitor scrolls near them.
  • Always set width and height attributes so the browser reserves space and the layout does not jump while images load.

Why it matters

Google’s Core Web Vitals include Largest Contentful Paint, which measures how quickly the main content, often a hero image, appears. Slow pages also lose visitors, especially on mobile data. Spending a minute compressing each image before upload pays off in speed, search visibility and lower hosting bandwidth.

Quick checklist

  1. Resize to about twice the display width.
  2. Use WebP or JPG for photos, PNG or SVG for graphics.
  3. Start at 75% quality and compare.
  4. Aim for under 200 KB for most content images.
  5. Add lazy loading and dimensions in your HTML.