How to Reduce JPEG Size Without Losing Quality
Updated March 2025•6 min read
"Lossy" vs "Lossless" — what does it mean? And how can you shrink a 5MB photo to 500KB while it looks exactly the same?
The Magic of JPEG Compression
JPEG is a "lossy" format. This means it was designed to be compressed. It works by grouping pixels of similar colors together and removing fine details that the human eye is bad at seeing anyway.
Does "Reducing Size" Mean "Resizing"?
Not always. There are two ways to make a file smaller:
- Resizing (Dimensions): Changing a photo from 4000x4000 pixels to 2000x2000 pixels. This drastically reduces file size because there are fewer pixels to store.
- Compressing (Data): Keeping the photo at 4000x4000 pixels, but optimizing the data storage. This is what we call "shrinking" the file size.
Recommendation
For the best web results, do both. Resize your image to the max width you need (e.g., 2000px), AND run it through a compressor.
When to use JPEG vs PNG?
- Use JPEG for: Photographs, portraits, complex scenes with millions of colors.
- Use PNG for: Logos, screenshots with text, graphics with sharp lines, or anything needing a transparent background.
Tools to Reduce JPEG Size
You can use expensive software like Photoshop, but for most users, a free online tool is faster and just as effective.