Detect the true file type of any file by reading its internal binary signature (magic bytes), independent of the file extension. Upload a file to instantly see its real MIME type and format description. Perfect for verifying mislabeled files, uncovering hidden formats, and ensuring security by checking actual content.
They are specific byte sequences at the very beginning of a file that identify its format. For instance, PNGs always start with 89 50 4E 47. Reading these bytes allows us to detect the file type regardless of the file name.
The file has been renamed with the wrong extension. The internal structure declares it as a PNG image. You should change the extension back to .png to ensure programs open it correctly.
It can detect a wide range of common types (~10 formats are checked via magic bytes). Very obscure or custom formats may be reported as “Unknown file type” if their signatures are not in the detection list.