How to reduce image file size
Key points
- 1. Resize → 2. Change format → 3. Lower quality
- Half the width and height ≈ a quarter of the size
- At quality 80 most people see no difference
When you hit an upload limit or a page loads slowly, it is time to shrink your images. Simply lowering quality tends to hurt the picture, but following the right order lets you cut file size a lot with no noticeable difference.
Step 1: resize to what you need
Pixel count has the biggest effect on file size. Phone photos are often over 4000 pixels wide, while 1200 to 1600 pixels is plenty for a blog post. Halving the width and height leaves a quarter of the pixels, and the file shrinks accordingly.
Set a max width in resize images to shrink them in one go, keeping proportions.
Step 2: choose the right format
- If photos were saved as PNG, switching to JPG or WEBP alone cuts them to a fraction.
- For images going on the web, WEBP is usually the lightest.
- For logos and icons, SVG is the lightest and sharpest.
Step 3: adjust the quality
JPG and WEBP let you set quality. Going from 100 to 90 saves a good amount, and at 80 most photos still look the same. Below 70, blotches start to appear in smooth areas like skies and skin. For images with a lot of text, stay at 85 or above.
In compress images, the percentage saved is shown as you change quality, so comparing is easy. If you have a hard limit, enter a target size and the right quality is found automatically.
How small is enough?
| Use | Rough target |
|---|---|
| Thumbnails, profile pictures | under 100 KB |
| Blog post photos | 150–400 KB |
| Full-screen background images | around 500 KB |
These are common rules of thumb, not fixed standards. Check on screen as you adjust.
A bonus: metadata is removed
Phone photos contain the date, device name and sometimes the location where they were taken. Images saved here don't include that information, which also helps strip personal details before posting photos online.