Binary Structure Parser

Binary structure parsing is the process of interpreting raw binary data by applying a structured template that defines how bytes should be grouped and interpreted. Unlike text-based formats where data is separated by delimiters, binary files store information as sequences of bytes at specific offsets with specific data types (integers, floats, strings). A binary structure parser reads these raw bytes and converts them into meaningful, human-readable values based on the template definition. This process is essential for understanding file formats, network protocols, firmware images, and any data stored in binary form. Our binary structure parser lets you define these templates interactively and see the decoded values instantly.

1. 1. Upload a binary file: Drag and drop any binary file (up to 50 MB), click to browse, or load the sample BMP data provided. All processing happens locally in your browser using the Web File API - your file never leaves your device.
2. 2. Define or choose a structure template: Select a pre-built template (BMP file header or PNG IHDR header) or create a custom template. Add fields with names, data types, offsets, and lengths. Each field tells the binary structure parser how to interpret the bytes at that position.
3. 3. Parse and inspect the results: Click "Parse Binary Structure" to decode the data. Our binary structure parser instantly displays a table with each field's raw hex bytes, decoded value, and interpretation. Switch to the hex dump view to see the raw byte layout alongside the parsed structure.

• Unsigned Integers (uint8, uint16, uint32, uint64): Whole numbers ranging from 0 to 2^(n)-1. uint8 is a single byte (0-255), uint16 is two bytes (0-65,535), uint32 is four bytes (0-4,294,967,295), and uint64 is eight bytes (up to 2^64-1). All multi-byte integers are read in little-endian byte order, which is the most common order in x86 and file formats.
• Signed Integers (int8, int16, int32, int64): Integers that can represent both positive and negative values using two's complement encoding. int8 ranges from -128 to 127, int16 from -32,768 to 32,767, int32 from -2,147,483,648 to 2,147,483,647, and int64 covers the full 64-bit signed range.
• Floating Point (float32, float64): Real numbers encoded in IEEE 754 single-precision (32-bit) and double-precision (64-bit) formats. float32 provides approximately 7 decimal digits of precision, while float64 provides approximately 15-17 decimal digits.
• Strings and Hex: The string type reads null-terminated ASCII text from the specified offset and length (stopping at the first null byte). The hex type displays the raw bytes as a hexadecimal string without any interpretation - useful for reserved fields, padding, or data you want to examine directly.

While our binary structure parser is a powerful tool for understanding binary formats, it has important limitations. The parser reads bytes sequentially according to your template - it does not automatically detect or parse complex structures like linked lists, variable-length records, or compressed data. All multi-byte values are read in little-endian byte order (LSB first), which covers most file formats but may not match big-endian formats like some network protocols or Motorola S-records. For very large files, the hex preview is limited to the first 256 bytes. String fields are interpreted as ASCII text; UTF-8 or other multi-byte encodings may not display correctly. For advanced binary analysis, combine this binary structure parser with tools like hex editors, disassemblers, and format-specific validators.