Question 1

How does image compression work?

Accepted Answer

This tool uses lossy compression to reduce image file size by reducing the amount of color and detail data stored in the file. The quality slider controls how much detail is preserved — higher quality means less compression and a larger file, lower quality means more compression and a smaller file. Most users cannot tell the difference between 80% and 100% quality on screen.

Question 2

What is the difference between lossy and lossless compression?

Accepted Answer

Lossy compression (used here) permanently reduces some image data to make the file smaller — the reduction is usually invisible at quality settings above 70–80%. Lossless compression (like PNG optimization) reorganizes the data without discarding any — the file size reduction is smaller but there is zero quality loss. This tool uses lossy compression for maximum size reduction.

Question 3

What image formats does this compressor support?

Accepted Answer

The compressor supports JPG (JPEG) and PNG files. WebP images are also supported — they are converted to PNG internally before compression. The output format matches the input format.

Question 4

Will compressing an image affect its dimensions?

Accepted Answer

No. Compression only reduces the file size by reducing the amount of color data stored — the pixel dimensions (width × height) remain exactly the same. A 1920×1080 image compressed from 2 MB to 400 KB will still display at 1920×1080 pixels.

Question 5

Are my images uploaded to a server?

Accepted Answer

No. All compression happens entirely in your browser. Your images are never sent to any server, never stored anywhere and never accessible to anyone other than you. This makes it safe to compress private, confidential or sensitive images.

Question 6

What quality setting should I use?

Accepted Answer

For most use cases — websites, emails, social media — a quality setting of 75–85% gives excellent visual quality with a 50–80% file size reduction. For print use, keep quality above 90%. For thumbnails and previews where quality matters less, you can go as low as 60–70%.

Question 7

How much can I reduce an image file size?

Accepted Answer

Results vary by image content. A high-quality JPG photo typically compresses to 30–50% of its original size at 80% quality with no visible degradation. Screenshots and PNG files with large areas of solid color compress more aggressively. The tool shows the exact compression ratio after processing.

Image Compressor

How to use Image Compressor

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