The internet's most complete file extension encyclopedia. Built for everyone who has ever received a file they couldn't open.
Why Filezeno exists and what problem we set out to solve.
Filezeno was born out of a frustration that everyone has experienced at some point: you receive a file, double-click it, and nothing happens — or you get an error you don't understand. You search online and find forum posts from years ago, manufacturer pages written for engineers, and vague answers that don't tell you which software to actually download.
We built Filezeno to fix that. One structured, accurate, up-to-date page for every file extension — covering what it is, what opens it on every platform, whether it is safe, and how to convert it if you need to. No paywalls. No registration. Just the answer.
Tens of thousands of file extensions exist. Most people recognize fewer than twenty of them.
A single authoritative reference, free to use, covering 10,000+ formats in complete depth.
10,000+ extensions documented across 8 categories in 9 languages, updated continuously as formats evolve.
To make file format knowledge universally accessible — for the student who can't open a school assignment, the office manager dealing with an unfamiliar attachment, the IT professional who needs platform compatibility details fast, and the developer referencing MIME types and format specifications.
Understanding file extensions should not require technical expertise. Filezeno makes it a ten-second lookup for anyone, in their own language, on any device.
Every entry in the Filezeno database follows the same complete structure — so you always know exactly what you will find.
Full name, who created the format, what type of data it stores, the MIME type, and a plain-English explanation of what the file actually contains and what it is used for.
Every extension has an explicit safety classification — Safe, Generally Safe, Medium Risk, or High Risk — with a clear explanation of actual risks and how to handle the file safely.
Compatible software listed for Windows, Mac, Linux, Android, and iOS — with free and paid options clearly marked. Every format has at least one free solution listed.
Filezeno is not a general-purpose search engine. It is a curated, maintained database where every entry is individually reviewed and structured the same way. When you land on an extension page you know exactly where to find what you need — no reading through paragraphs to find the software name buried at the end.
We cover 10,000+ formats thoroughly rather than listing thousands superficially. A page that actually answers your question is worth more than ten pages that don't.
Available in English, Spanish, French, German, Italian, Portuguese, Arabic, Chinese, and Japanese. The same database, the same accuracy, in your language.
Filezeno's database is built and maintained by people with real, hands-on experience working with file formats across every platform — not auto-generated content.
Our editorial team brings together expertise from systems engineering, IT support, digital security, and technical writing. Every contributor has spent significant time in the real world dealing with the exact problems our users are trying to solve.
Systems Engineer and Format Research Lead. 12 years cross-platform experience. Has personally reviewed every extension in the Filezeno database.
Specialists who classify risk levels for executable and high-risk formats based on documented attack vectors and published security research.
Writers who translate complex format specifications into clear, plain-English explanations readable by anyone, regardless of technical background.
Reviewers for all 9 supported languages who ensure technical terminology is accurate and natural in every language version of the site.
Filezeno operates by a clear set of principles that govern every editorial and product decision we make:
Found an error in our database? Know a format we haven't covered? We genuinely want to hear from you.
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