Okteta is a simple editor for the raw data of files.

Features
 *  Values and characters shown either in two columns (the traditional display
    in hex editors) or in rows with the value on top of the character
 *  Editing and navigating similar to a text editor
 *  Customizable data views
 *  Data view profiles
 *  Tools dockable on all sides or floating
 *  Numerical encodings: Hexadecimal, Decimal, Octal, Binary
 *  Character encodings: All 8-bit encodings as supplied by Qt, EBCDIC
 *  Fast data rendering on screen
 *  Multiple open files
 *  Support for remote files, by http, ftp, fish & other protocols supported by
    KDE Platform
 *  Export of data to text, both file and clipboard.
 *  Checksum/Hashsum calculator: Modular sum (8/16/32/64 bit), Adler-32, CRC-32
    and Hashsums by the QCA2 library, can be SHA-0/1/224/256/384/512, MD2/4/5,
    RIPEMD-160, Whirlpool
 *  Structures tool for analyzing and editing based on user-creatable structure
    definitions
 *  Statistic tool
 *  String extraction tool
 *  8-bit charset conversion tool
 *  Decoding table listing common simple data types.
 *  Bookmarks
 *  Printing
 *  Table with complete list of all byte values

WWW: https://www.kde.org/applications/utilities/okteta/