What is LSB?
Least Significant Bit (LSB) is the rightmost bit in a binary number - it has the smallest impact on the overall value.
Example:
11010110 → The 0 at the end is the LSB
11010111 → Changed to 1 - only changes value by 1!
In images, changing the LSB in color values (0-255) creates invisible changes to the human eye:
Red: 200 vs 201 - You can't tell the difference! 🎨
📊 Storage Capacity
- Each pixel has 3 color channels: Red, Green, Blue
- Each channel provides 1 LSB for hiding data
- 1 pixel = 3 bits of hidden storage
Your Image:
Upload an image to see calculations
📐 The Math
🏗️ v3 Format Architecture
This tool uses a two-layer encoding system for reliable detection and optimal capacity:
Layer 1: Fixed Sentinel (1-LSB)
First 19 pixels always use 1-LSB to store:
- Magic number (0xAA55) for format detection
- LSB mode used for message (1-4 bits)
- Message length (up to 4GB)
Layer 2: Variable Message (N-LSB)
Remaining pixels use the optimal LSB mode for your message size.
🚀 Multi-bit LSB Modes
The tool automatically selects the minimum LSB mode needed (you can override):
| Mode |
Capacity |
Visual Impact |
Overhead |
| 1-LSB |
Baseline |
Invisible (±1) |
7 bytes |
| 2-LSB |
2× capacity |
Barely visible (±3) |
7 bytes |
| 3-LSB |
3× capacity |
Slight noise (±7) |
7 bytes |
| 4-LSB |
4× capacity |
Visible degradation (±15) |
7 bytes |
Auto-Selection Strategy: The tool always chooses the lowest LSB mode that fits your message, prioritizing stealth over capacity. The fixed sentinel (7 bytes) ensures reliable detection regardless of mode.