Guides
Practical answers to the file problems people run into most, with real measurements from our own converters.
How to open HEIC photos on Windows (and convert them to JPG)
Why iPhone photos arrive as HEIC files, four ways to deal with them on Windows, and what size of JPG, PNG or PDF to expect when you convert one (we measured it).
Read the guide →How to reduce a PDF's size to send it by email
Why some PDFs are huge, what each compression level really does (we measured a 7.4 MB PDF going down to 310 KB), and what to do if it is still too big.
Read the guide →How to extract the audio from a video (MP4 to MP3)
Save the soundtrack of a video as MP3 or another audio format, see how small the audio file is compared with the video (we measured every format), and pick the right quality.
Read the guide →JPG or PNG? Which image format to use and when
The real difference between JPG and PNG, measured on 17 photos and 3 screenshots: which one suits photos, screenshots, logos and the web.
Read the guide →What is a WebP file and how do you open it?
Why images saved from websites end up as WebP, which programs open it, and what happens to size and quality when you turn it into JPG or PNG.
Read the guide →How to make your website's images lighter without losing quality
We cut 17 phone-sized photos from 1.5 MB to as little as 56 KB each. The right order of steps, the sizes to use and the one mistake that undoes the savings.
Read the guide →How to convert an SVG logo to PNG at the right size
Why many apps want PNG instead of SVG, how to keep the transparent background, and how to get a sharp PNG at exactly the size you need, tested on our own logo.
Read the guide →MP4 vs MOV: what's the difference and which should you use?
Why iPhones record MOV, why many apps prefer MP4, and what we measured when converting: an identical copy in 0.2 seconds, or a re-encode when you need one.
Read the guide →How to make a GIF from a video
Turn a short clip into an animated GIF that plays everywhere, see how fast GIF size grows with length (we measured it), and know when a video is the better choice.
Read the guide →MP3, WAV or FLAC: which audio format should you use?
What separates lossy, uncompressed and lossless audio, measured on one song in every format, which suits listening, editing and archiving, and how to convert.
Read the guide →How to edit a PDF in Word (and when it won't work)
What really happens when a PDF becomes a Word document, tested on a real file: what you can edit easily, what you can't, and the better route for big changes.
Read the guide →How to turn photos of documents into a single PDF
Photograph a multi-page document with your phone, convert each picture to PDF and combine them into one file, and see how small it can get (we measured it).
Read the guide →How to export an Excel sheet to CSV without losing data
What a CSV keeps and what it drops, tested with a workbook full of traps: leading zeros, dates, accents, formulas and a second sheet. Plus what happens the other way.
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