Hintfo is a metadata viewer. It shows you the hidden hints and internal information contained within files.
To use Hintfo, simply upload a file. It will display the metadata associated with the file.
There are a wide range of file formats and many different metadata viewers. Not every metadata viewer works on every file. Moreover, different metadata viewers may show different information or the same information in different ways.
Hintfo automatically identifies which tools to use in order to extract the most informative information.
About Metadata
All files contain some kind of data about the data (metadata).
Most of the time, metadata exists as background information that is hidden inside the file or associated with the file. There are different types of metadata:
Category
Purpose
Examples
Implicit
Metadata can be implicit and determined from the file encoding properties.
A picture's dimensions or an audio file's sample rate are required for properly processing the file's format.
The file's size and checksums are computed from the file's contents, but not explicitly stored inside the file.
Explicit
Metadata may be explicit, such as a chunk of data that describes specific file properties. These are not required for decoding the file format.
These are often found in data structures like "EXIF", "ICC Profile", or "XMP".
These structures may record information such as the camera settings, author's name, or application information.
External
Metadata can also be external to the file's content.
The file's name, last modified time, and access permissions (read only, read-write, etc.) apply to the file but do not alter the file's contents. For example, you can rename a file without changing the internal contents.
Conflicting Metadata
Not all metadata is limited to one of these categories. For example:
The Multipurpose Internet Mail Extensions (often called the MIME type, mimetype, or just 'mime') helps applications determine how to handle a file format. A JPEG file (MIME type "image/jpeg") may be directed to a picture viewer, while an MP3 file (audio/mp3) may be opened with a music player. The MIME type may be determined from the file structure (implicit), recorded in an internal metadata field (explicit), or determined from the file's name (external; a file name ending with ".jpg" file is typically handled a JPEG).
The file's size (number of bytes in the file) is both implicit and external. It is implicit because it is derived from the file contents. It is external because the file system can provide this information without explicitly counting every byte in the file.
When metadata may come from different sources, it may not always be consistent. For example, usually a file's name that ends with ".jpg" contains JPEG-encoded data. The MIME type based on the file's name and structure should all be "image/jpeg". However, the file can be renamed and does not need to retain the ".jpg" suffix. A file named "file.png" may have a filename MIME type of "image/png" but a file strucuture of "image/jpg". Moreover, your web browser may specify the file's mime type to the web server during a file upload. Your uploaded MIME type may not match the file's internal structure.
Even different metadata viewers may show conflicting MIME type values. For example, some Apple iPhones and Android devices use an image format called HEIC or AVIF. (AVIF is the open source version of HEIC.) The file "mypicture.heic" and identified as an "image/heic" based on the filename. However, your web browser may identify the uploaded format as "image/heif", the file format may not be identified by a basic structural analysis (defaulting to "application/octet-stream"), ExifTool may determine the file to be an "image/avif", and Exif2 may recognize it as a "video/quicktime". (Which one is correct? It depends on the file.)
About Hintfo
Metadata often provides essential information about the file's structure and handing. However, it may also contain descriptive information related to the file's creation. This may include GPS coordinates, timestamps, and unique identifiers. Hintfo shows you these hidden hints and internal information contained within files.
Privacy Policy
Uploaded files are cached for about 20 minutes. Otherwise, we don't keep copies unless the uploaded file caused a problem with this service.
This service retains:
Typical web logs (timestamp, IP address, URL accessed, web browser type, etc.). This is used for debugging issues and identifying potential attacks.
A summary of the type of file uploaded (MIME type). If we see widespread interest in a particular type of file format that is not supported very well, then we might add in better support for that format.
Copies of any file that causes a server error. (Sometimes people intentionally upload hostile files in an attempt to compromise the server. We will retain these files and ban the user.)
This service uses cookies and TLS sessions. The cookie identifies your session and your uploads are linked to your session. When your session expires, the information about the upload is removed.
For Law Enforcement
Uploaded content and session information is automatically deleted when the cache expires (about 20 minutes). Even if you serve us with a warrant, we have no method of identifying uploaded content after it is deleted. Beyond the logs mentioned above, we do not collect user information. Moreover, there is no guarantee that we will retain web logs for any particular duration.
Contact
This free service is provided by Hacker Factor.
If you have questions, please see the Hacker Factor contact page.