Hide confidential text messages and files inside images using Least Significant Bit LSB encoding and hardware-accelerated AES-GCM encryption.
Start with a small test message so you can verify encoding and decoding before using larger payloads.
Use the actual downloaded PNG, not a screenshot or a JPEG conversion. LSB payload bits depend on the stored pixel values.
Encryption adds overhead, so compare the displayed payload size with capacity. Concealment does not guarantee that an image is undetectable as steganography.
Resizing, recompression, social-media processing, or pixel edits can destroy the payload. Keep an independent backup of anything important.
The Free Steganography Tool is an advanced client-side cryptographic and digital concealment studio that hides secret messages and confidential files inside harmless digital images. While standard encryption obscures data into obvious ciphertext blocks that immediately draw suspicion from censors and network monitors, steganography conceals the very existence of the communication. By encoding binary payload bits into the Least Significant Bits (LSB) of image pixel color channels, the host image appears visually identical to the naked human eye.
Security and confidentiality are reinforced through integrated AES-GCM 256-bit encryption powered directly by the browser Web Crypto API. Before embedding into image pixels, your secret text or binary attachment is encrypted with a user-supplied passphrase using PBKDF2 key derivation with 100,000 iterations and a cryptographically random salt. An unauthorized observer analyzing the pixel bitstream cannot decipher or prove the presence of hidden data without the secret passphrase.
Enjoy complete privacy with zero server uploads: all image decoding, pixel canvas manipulation, encryption, and extraction algorithms execute 100% locally in your browser memory. Calculate storage capacities based on image dimensions, encode payloads into lossless PNG outputs, and extract hidden secrets from received carrier images effortlessly.
Choose Encode to hide secret text or files within a cover photo, or Decode to extract hidden payloads from a carrier stego-image.
Import a high-resolution PNG or lossless image. The tool calculates your maximum payload byte capacity based on pixel resolution.
Type your message or attach a secret file. Optionally enable AES-GCM 256-bit encryption with a master password for layered defense.
In Encode mode, download the pristine carrier PNG. In Decode mode, enter the passphrase to decrypt and read the recovered secret.
Modifies the lowest-order bit of RGBA pixel bytes to embed binary data without introducing perceptible visual discoloration or noise.
Encrypts payloads using authenticated AES-GCM via the Web Crypto API with PBKDF2 key stretching before embedding.
Measures carrier image dimensions and displays exact bit capacity, preventing payload overflow and corruption.
Executes all canvas pixel manipulation in local device RAM, ensuring private messages and cover images never transit the network.
Steganography hides the existence of communication rather than just encrypting text. Always export as lossless PNG because lossy JPEG compression destroys hidden LSB bits.
Round-trip a short demonstration message and observe how lossless export preserves the payload.
Check whether a planned image workflow preserves an encoded test message. Keep separate backups rather than using a hidden image as the only store.
| Encoding Mode | Bit Depth & Channel Allocation | Storage Capacity (per 1MP photo) & Detectability |
|---|---|---|
| 1-Bit LSB (Stealth) | 1 bit in R, G, B channels (3 bits/px) | ~375 KB / MP; completely undetectable to human eye and basic chi-square |
| 2-Bit LSB (Balanced) | 2 bits in R, G, B channels (6 bits/px) | ~750 KB / MP; imperceptible noise in textured photos, higher payload |
| AES-GCM 256 Layer | PBKDF2 100k iter + 128-bit IV auth tag | Transforms payload into uniform random noise prior to pixel embedding |
| Magic Header (32-bit) | Fixed 4-byte signature + length prefix | Allows extraction decoder to identify presence and length of hidden data |
| PNG Lossless Format | Deflate compression (RFC 1951) | Crucial: preserves exact raw pixel values without DCT lossy corruption |
JPEG uses lossy discrete cosine transform compression that alters pixel values and discards high-frequency data during saving, which immediately corrupts the Least Significant Bits holding the hidden secret. Lossless PNG preserves every exact pixel byte unmodified.
Visually, an LSB-encoded image is identical to the original because changing the lowest bit alters color intensity by at most 1/255th. However, sophisticated statistical chi-square analysis can detect anomalies unless AES-GCM encryption is used, which makes the bit distribution appear as pure uniform noise.
Each pixel contains 3 usable color channels (Red, Green, Blue). Embedding 1 bit per channel yields 3 bits per pixel, or approximately 375 kilobytes of hidden capacity for every 1 megapixel of image resolution.
An internet connection is required to open tools and refresh a temporary session. Processing stays on your device; the handshake sends a random challenge, not files or text inputs. Libraries, fonts or models may download. Local processing cannot remove risks from an untrusted device or extension.
