If you are scanning documents for printing, use 300 DPI. A colour A4 page at 300 DPI will be about 1.2 MB as a JPG. That keeps text and images sharp on paper. If you only need to view or email the file, drop to 150 DPI; the same page becomes roughly 150 KB in greyscale, which is small enough to attach anywhere.
GekiPDF takes your JPG or PNG files and makes one PDF page per image. You can drag them into order before converting. For phone photos of documents, tick the optional A4 fit so they fill the page properly. Files up to 50 MB are accepted, and you get 40 conversions per hour from your IP address.
Frequently asked questions
What is the minimum DPI for readable text on screen?
Use at least 100 DPI for screen viewing. At 72 DPI, small text may blur when zoomed. For comfortable reading without zooming, 150 DPI is safe.
Will a 600 DPI scan make my PDF clearer on screen?
No. Screens show about 96-110 pixels per inch, so anything above that is wasted. A 600 DPI scan just creates a larger file with no visible benefit on screen.
How do I reduce file size after scanning?
Re-scan at a lower DPI rather than compressing later. Compressing a high-DPI image often adds artefacts while keeping the large pixel count. Start at the right DPI for your output.
Do it in the full tool
Open JPG to PDF for all options, or jump straight to another step below.
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