1. Make it smaller in pixels
Phone photos are often 4000 pixels wide or more, far bigger than any screen needs. Halving the width and height cuts the file to about a quarter. 2000 pixels on the longest side is plenty for email and most websites; 1200 is enough for a blog or social post. Resize Image does this, or set a maximum size in the compressor.
2. Pick the right format
- Photos: JPG, or WebP for websites.
- Screenshots, logos and graphics: PNG.
- Photos saved as PNG are several times larger than they need to be; convert them to JPG.
3. Compress
Compress JPG at quality 70–80 usually shrinks a photo by more than half with no visible difference. Compress PNG reduces graphics to fewer colors, often cutting 60–80% while keeping transparency.
Hitting an exact limit
For a limit such as "under 500 KB", type it in Target size in Compress Image. The highest quality that fits is chosen for you.
What not to do
Do not compress the same JPG again and again: each save loses a little more detail. Keep the original and compress a copy.
A worked example
A 12-megapixel phone photo is 4032 × 3024 pixels and often around 3 MB as a JPG. Resizing it to 2000 × 1500 leaves about a quarter of the pixels, which brings it to roughly 750 KB. Compressing at quality 75 then usually takes it to around 300 to 400 KB. The exact figures depend on the picture: a detailed scene of leaves compresses less than a plain sky.
Common problems
- The file got bigger. The original was already well compressed, or a quality higher than the original's was chosen. Lower the quality or resize as well.
- The transparent background turned white or black. JPG has no transparency. Keep logos and cut-outs as PNG or WebP.
- Text in a screenshot looks smudged. JPG blurs sharp edges. Use PNG for screenshots, and reduce colors rather than quality.
- Colors look duller. Photos from recent phones use a wider color range, and removing the color profile can flatten them. Keep the profile when there is an option to.
- The photo turned sideways. Phones often store a sideways image with a tag saying how to rotate it. Some editors drop the tag when they resize; rotate it back before compressing.