Any task with a file — open, compress, convert, edit or repair — is solved with the right tool. The problem is that there are thousands of tools: online services, desktop programs, browser extensions, command-line utilities. Without a guide it is easy to install a heavy “combine” where a single button would have been enough, or to upload a private document to a dubious site.
This page is a navigator through the world of file tools. We split them into five working categories, explained when each is needed, and gathered links to detailed breakdowns.
Upload a file and solve your task without installing any programs. Some tools process files locally and send nothing to the server.
Before you google “how to open .heic” or “how to compress a PDF”, answer four questions for yourself — this narrows the choice right away.
Viewing — you need a viewer. Changing the format — a converter. Changing the content — an editor. Reducing the size of a batch — an archiver.
A contract, a passport scan, a work database — such files are better not uploaded to someone else's servers. For them, choose desktop programs.
A one-off task — use an online service. A regular one — install a program or learn a CLI utility.
A “Convert” button suits most people. If you are a developer and want to automate — look toward the command line.
A converter takes a file in one format and returns it in another: PDF to Word, PNG to WebP, video to audio. This is the most in-demand category.
When you need it: you received a file that won't open; you need to upload a document to a system that accepts only a certain format; you want to reduce the weight of an image by changing its format.
What to look at: preservation of quality; batch processing; privacy (for confidential documents — offline tools).
➡️ Detailed review: 10 free online file converters (2026)
An archiver solves two tasks: packing many files into a single container and compressing. ZIP, 7z, RAR, tar.gz — these are all archive formats.
When you need it: you're sending a folder with dozens of files; you downloaded a .rar or .7z and can't open it; you want to shrink a large archive of documents.
What to look at: format support (at least ZIP and 7z); compression ratio; encryption (AES-256 for sensitive data).
Already compressed formats (JPEG, MP4, MP3) will barely shrink with an archiver. The real savings are on texts, spreadsheets and source code.
A viewer simply shows a file's content — with no way to change anything. It saves the day when there is no “native” program.
When you need it: open a rare format “just to look”; quickly flip through a file without installing a heavy program; view it on someone else's computer without administrator rights.
What to look at: breadth of formats; speed; safety (“view only” mode doesn't run macros).
An editor changes a file's content itself. The category splits by the type of content:
From “Notepad” to full-fledged IDEs. For code — with syntax highlighting, autocompletion and encoding support (UTF-8 versus Windows-1251 is a frequent source of garbled characters).
Change images: cropping, retouching, layers, color correction.
Edit text right inside a PDF, merge and split documents, add signatures, fill in forms.
Cut, join, apply effects, change volume and format.
A whole separate universe of tools — for those who work with files as data and code.
➡️ Related materials: Where to get code templates and boilerplate.
| Criterion | Online tools | Desktop / CLI |
|---|---|---|
| Installation | Not needed | Needed |
| Startup speed | Instant | Slower |
| File privacy | File goes to a server | File stays with you |
| Volumes and batches | Limited | Practically without limits |
| Working offline | No | Yes |
| Automation | Rarely | Yes (scripts, CLI) |
The rule is simple: a public or “one-off” file — use an online service. A private document, a large volume or a regular task — desktop or the command line.
A converter changes a file's format without touching its meaning. An editor changes the content itself — text, image, sound.
For public files — yes. For private ones — offline programs are better: an uploaded file physically ends up on someone else's server.
In most cases, no. There are plenty of free converters, archivers, viewers and editors for everyday tasks.
One that supports ZIP and 7z and can unpack RAR. This set is enough in 99% of cases.
Tools
Need to convert a document, image or video to another format right in the browser? We gathered trusted services — with no installation or registration.
Resources
A map of trusted resources and a breakdown of the MIT, CC0, Apache, OFL licenses: where to legally get icons, fonts, UI kits, datasets and stock media.
Resources
Don't want to build a project structure from scratch? We gathered trusted boilerplate sets for frontend, backend and quick prototypes.
File tools fall into five clear categories: converters change the format, archivers pack, viewers show, editors edit the content, and developer utilities work with a file as data. The choice comes down to two questions: what you're doing with the file and how private it is.
A comparison of free online services, their limits and what's important to know about the safety of uploading files.