Guides
How to change a file extension, type, or format
To change a file's extension you rename it; to change its actual format you convert it. Here's how to do each on Windows and Mac, and how to tell which one you need.
Vashist Nagori··7 min read
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The ChangeMyFile Blog
Notes on file formats, conversion, and the tools we build.
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Formats
Does converting MP4 to MP3 lose quality? We measured it
The audio in an MP4 is usually AAC, and converting AAC to MP3 re-encodes it with a second lossy codec, so a little quality goes every time. Here's what we measured with our own converter, and the one case where you can skip the loss entirely.
Vashist Nagori··4 min read
Guides
How to compress a PDF without wrecking the images
Big PDFs are almost always photos stored at print resolution. We compressed an 18.40 MB test file to 1.58 MB with our own tool and measured every setting; here's how to shrink yours without ruining scans or print quality.
Vashist Nagori··4 min read
Guides
How to convert MTS to MP4 without losing quality
An MTS file holds plain H.264 video, so converting it to MP4 is usually repackaging, not rebuilding. Here's how to do it in seconds with zero quality loss, and the two cases that genuinely need more.
Vashist Nagori··5 min read