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Straight explanations of how file formats actually work, so you can make a decision rather than guess at a setting.

How to compress a PDF without losing quality

Most oversized PDFs are large for one specific reason. Find it first and you can often shrink the file with no visible loss at all.

5 min read

JPG vs PNG vs WebP: which format to use and when

Three formats, three different compromises. Which one is right depends less on quality than on what the image contains.

5 min read

Are online PDF and image tools safe? How to check

You can settle the question yourself in about thirty seconds, without taking anyone's word for it. Here is the test.

5 min read

How to reduce image size for email attachments

Attachment limits are smaller than they look, and the fix is usually resizing rather than compressing. The difference matters.

4 min read

How to merge, split and reorder PDF files

Combining and rearranging PDFs is lossless if the tool does it properly. Here is what "properly" means, and how to tell.

5 min read

Image resolution and DPI, explained properly

DPI is one of the most misunderstood numbers in imaging. For screen work it means nothing at all — and knowing why makes sizing decisions obvious.

5 min read

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