File Type Detector
Identify any file — even without an extension, or with the wrong one.
Drop one or more files
they are only read on your device
● Your files are processed locally in your browser and are not uploaded to our servers.
How it works
Most file formats start with a fixed sequence of bytes called a signature or magic number: PNG files begin with 89 50 4E 47, PDFs with %PDF. KadiTools compares the first bytes against about 60 known signatures, tells ZIP-based formats apart (DOCX, XLSX, EPUB, APK…) and recognizes text formats like JSON, CSV, HTML and SVG. It then warns you when the extension doesn't match the content — a common trick in malicious attachments.
FAQ
Is a file safe if the type matches?
Not necessarily — the type tells you what the file is, not whether it's harmful. Don't open executables you didn't expect.