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Guides & how-tos.

Practical guides on file conversion, compression, and editing — no software required.

Guides on converting, compressing and editing files — written for people who want the thing done, not a lecture on codecs.

Every guide here is about something you can do in this browser tab, for free, without uploading anything. Where a guide says a format will save you 80%, that figure came from converting an actual file and reading the result — not from a spec sheet. The methodology page covers how that testing works and what it can’t tell you.

Nine guides so far, covering images, video and audio. Documents are next.

Why Your Resized Image Never Looks Right Again
Shrink an image and scale it back up and it's ruined. Not a bug — here's what resizing actually does to your pixels, and why nothing can undo it.
Why Does Everyone Hate HEIC?
HEIC makes smaller photos than JPG and almost nobody likes it. The reason isn't technical — it's a patent licensing story, and AVIF proves it.
MP4, MKV, MOV, AVI — What's the Actual Difference?
They aren't really video formats — they're containers. Here's what that means, and why one conversion takes two seconds and another takes ten minutes.
How to Compress a Video Without Losing Quality
Large video files are a pain to share and store. Learn how to shrink them significantly while keeping them looking sharp.
How to Reduce Image File Size Without Losing Quality
Large image files slow down websites and clog email attachments. Here's how to shrink them by 80%+ with no visible quality loss.
What is AVIF? The Image Format You Should Know About
AVIF is the newest image format on the web — smaller than WEBP, better than JPG, and gaining fast. Here's what it is and when to use it.
Best Image Format for Websites in 2026
JPG, PNG, WEBP, AVIF — which format should you actually use on your website? Here's a straight answer backed by the numbers.
What is MIDI? A Beginner's Guide to the Music Format
MIDI isn't audio — it's musical data. Learn what MIDI files actually contain, how they differ from MP3 and WAV, and what you can do with them in a DAW.
How to Remove a Watermark From a Photo — Free, In Your Browser
The clone stamp approach that actually works — sample clean pixels nearby and paint them over the watermark. No AI guessing, no blurring.

How these guides are written

Each one solves a specific problem and links to the tool on this site that does it. No affiliate links, no “download our software”, no ten paragraphs of preamble before the answer — the fix is near the top and the explanation follows for anyone who wants it.

The numbers are the part that takes the longest. When a guide claims lossless WebP beats PNG on screenshots, that’s because a 243 KB screenshot came out at 65 KB when it was actually tested. Where the result was unflattering — conversions that make files bigger, formats that aren’t worth switching to — the guide says so.

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