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+# Viewing Raw Data in Hex or Binary on macOS / Linux / Windows (CLI Guide)
+
+Inspecting raw bytes is essential for debugging, reverse-engineering, verifying file formats, or examining file headers.
+This guide introduces common command-line tools to display file contents in **hexadecimal** or **binary**, and how to limit output to a specific number of bytes.
+
+---
+
+## macOS & Linux
+
+macOS and Linux share most Unix tools, so their usage is nearly identical.
+
+---
+
+## 1. `hexdump`
+
+### Hex output
+
+```sh
+hexdump -C file.bin
+```
+
+* `-C` → canonical hex + ASCII view (similar to `xxd`)
+
+### Limit output to N bytes
+
+#### First 16 bytes
+
+```sh
+hexdump -C -n 16 file.bin
+```
+
+#### 16 bytes from offset 32
+
+```sh
+hexdump -C -s 32 -n 16 file.bin
+```
+
+* `-s OFFSET` → seek to offset
+* `-n BYTES` → read N bytes
+
+---
+
+## 2. `xxd`
+
+### Hex output
+
+```sh
+xxd file.bin
+```
+
+### Binary output
+
+```sh
+xxd -b file.bin
+```
+
+### Limit output to N bytes
+
+#### First 16 bytes
+
+```sh
+xxd -l 16 file.bin
+```
+
+#### 16 bytes from offset 32
+
+```sh
+xxd -s 32 -l 16 file.bin
+```
+
+#### First 16 bytes in binary
+
+```sh
+xxd -b -l 16 file.bin
+```
+
+---
+
+## 3. `od` (POSIX standard)
+
+### Hex output
+
+```sh
+od -Ax -t x1 file.bin
+```
+
+### Binary output
+
+```sh
+od -An -t b1 file.bin
+```
+
+### Limit output to N bytes (hex)
+
+```sh
+od -Ax -t x1 -N 16 file.bin
+```
+
+### Limit output to N bytes (binary)
+
+```sh
+od -An -t b1 -N 16 file.bin
+```
+
+---
+
+## 4. `hd`
+
+Available on macOS via Homebrew (`brew install hexedit`) or on Linux (util-linux).
+
+```sh
+hd file.bin
+```
+
+---
+
+# Windows
+
+---
+
+## 1. PowerShell: `Format-Hex` (built-in)
+
+### Hex output
+
+```powershell
+Format-Hex file.bin
+```
+
+### Limit output to N bytes
+
+#### First 16 bytes (hex)
+
+```powershell
+Get-Content file.bin -Encoding Byte -TotalCount 16 | Format-Hex
+```
+
+#### First 16 bytes (binary)
+
+```powershell
+Get-Content file.bin -Encoding Byte -TotalCount 16 | ForEach-Object {
+    [Convert]::ToString($_, 2).PadLeft(8, '0')
+}
+```
+
+---
+
+## 2. CertUtil (hex only)
+
+```cmd
+certutil -dump file.bin
+```
+
+CertUtil cannot directly limit byte count, but you can limit lines using a Unix-like environment (Git Bash/MSYS2/WSL):
+
+```sh
+certutil -dump file.bin | head -n 5
+```
+
+---
+
+## 3. Windows Subsystem for Linux (WSL)
+
+WSL allows you to use all Linux tools:
+
+```sh
+xxd -l 16 file.bin
+```
+
+---
+
+# Summary Table
+
+| Platform | Hex Output                      | Binary Output             | Limit Output Size               |
+| -------- | ------------------------------- | ------------------------- | ------------------------------- |
+| macOS    | `xxd`, `hexdump -C`, `od -t x1` | `xxd -b`, `od -t b1`      | `hexdump -n`, `xxd -l`, `od -N` |
+| Linux    | same as macOS                   | same as macOS             | same as macOS                   |
+| Windows  | `Format-Hex`, `certutil -dump`  | PowerShell bit conversion | `Get-Content -TotalCount`       |
+| WSL      | Linux tools                     | Linux tools               | Linux tools                     |
+
+---
+
+# Quick Examples
+
+### Print first 32 bytes in hex
+
+```sh
+xxd -l 32 file.bin
+```
+
+### Print bytes starting at offset 0x100
+
+```sh
+hexdump -C -s 0x100 -n 64 file.bin
+```
+
+### Print first 10 bytes in binary (Linux/macOS)
+
+```sh
+od -An -t b1 -N 10 file.bin
+```
+
+### Print first 16 bytes in binary (Windows PowerShell)
+
+```powershell
+Get-Content file.bin -Encoding Byte -TotalCount 16 | % { [Convert]::ToString($_,2).PadLeft(8,'0') }
+```
+
+> Generated By ChatGPT-5.1