Keep the current dimensions and change only the encoding settings. JPG and WebP respond to quality controls; PNG remains lossless in this workflow, so its size may not fall as dramatically. Open Compress Image.
Pixel dimensions and file size are separate
An image can stay 2400 × 1600 pixels while its file size changes substantially. The number of pixels controls the canvas dimensions, while the format, compression method, quality setting, transparency, and visual complexity influence how many bytes are needed to store those pixels.
That means resizing is not required when the image already has the correct dimensions for the destination. Compression can create a lighter copy of the same width and height.
Use JPEG or WebP quality controls for lossy compression
JPEG and WebP can trade some visual fidelity for smaller files. Lowering quality generally reduces file size, but the relationship is not linear and the same setting can look different across photographs, illustrations, text, and gradients.
Preview important details at the size people will actually see them. A small saving is not useful if text becomes difficult to read or fine edges develop obvious artifacts.
- JPEG is widely compatible for photographs.
- WebP is useful for modern web delivery and can also preserve transparency.
- Keep the original source when repeated exports may be needed later.
Why PNG often behaves differently
PNG is lossless in the current compression workflow. There is no lossy quality slider that throws away visual information in the same way as JPEG or WebP. File-size savings therefore depend more on the actual image content and the encoding result.
Screenshots, flat graphics, and transparent assets may still belong in PNG. Photographic PNG files, however, can be much larger than a carefully encoded JPEG or WebP delivery copy.
Compare the actual output bytes before choosing a setting
The best compression setting is the one that meets the destination requirement while keeping acceptable visual quality. Compare the output file size, inspect the image, and avoid assuming that one quality number is ideal for every file.
For a batch, use shared settings as a starting point and switch to individual overrides for images that need a different format or quality level.
Common questions
Does compression change image dimensions?
The Compress Image tool keeps the decoded width and height unchanged. It changes the output encoding and quality settings.
Which is smaller, JPG or WebP?
It depends on the source and chosen quality. Compare real outputs rather than assuming one format always wins.
Can I compress PNG with a quality slider?
PNG remains lossless in this workflow, so the JPEG/WebP-style lossy quality control does not apply to PNG output.
Should I resize as well as compress?
Only when the pixel dimensions are larger than the destination needs. If dimensions are already correct, compression alone may be enough.