Guides
Why a PNG is ten times the size of a JPEG. What a container is, and why it is not a video format. Where your spreadsheet’s leading zeros went. Written to be useful whether or not you convert anything afterwards.
- Images7 min read
Why your PNG is so much bigger than your JPEG
The same photograph can be 300 KB as a JPEG and 4 MB as a PNG. Here is what each format is actually doing, and how to tell which one your file wants to be.
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- Images5 min read
Where your transparent background went
Transparency is the property most often lost silently in a conversion — the file looks perfect until it lands on a coloured background and grows a white rectangle.
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- Video7 min read
MP4, MOV and MKV are not really video formats
The extension on a video file tells you far less about it than most people assume. Understanding the difference between a container and a codec explains almost every confusing thing about video conversion.
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- Documents6 min read
Why your CSV lost its leading zeros
A CSV is text with no types, and a spreadsheet has to guess what each column means. That guess is where postcodes, product codes and dates quietly get damaged.
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- Documents5 min read
Word to PDF: what survives, what moves and what disappears
The conversion that looks simplest is the one that quietly shifts a line break and pushes your last paragraph onto a page of its own. Here is what actually happens, and what to look at afterwards.
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- Images5 min read
The data hiding in your photos, and what conversion does to it
Every photo from a phone carries a record of the camera, the settings, the time and often the exact place it was taken. Here is what is in there, how it leaks, and what happens to it when you convert the file.
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- Images5 min read
WebP or AVIF: choosing a modern image format
Both beat JPEG comfortably. They differ in how much they beat it by, how long they take to produce, and what will refuse to open them.
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- Audio6 min read
What 192 kbps actually means, and when you need more
Bitrate is the single dial that decides how big an audio file is and how good it sounds. Here is what the numbers mean, why they are not comparable between codecs, and where the real thresholds sit.
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- Documents5 min read
Why you cannot copy text out of a scanned PDF
Two PDFs can look identical and be completely different files. One contains text; the other contains a photograph of text. Only one of them can be searched, copied or converted to Word.
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- Video5 min read
GIF is a terrible video format, and sometimes the right one
A three-second GIF can be larger than the minute-long video it came from. Here is why that happens, and the narrow set of cases where GIF still wins anyway.
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- Documents5 min read
Turning PDF pages into images without regretting the resolution
A PDF page has no resolution until you render it. The number you choose at that moment is the one you are stuck with, so it is worth choosing deliberately.
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- Archives5 min read
ZIP, TAR.GZ and 7z: which archive format, and why
The archive formats differ in one structural way that explains almost everything else about them: whether they compress each file separately or all of them together.
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- Documents5 min read
Converting presentations without breaking them
A slide deck carries more than the slides. Knowing which parts have somewhere to go in the destination format is the difference between a clean conversion and finding out on stage.
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