Base91 Encoder & Decoder

Securely encode text to highly efficient basE91 formats or decode existing binary representations locally in real-time

Source Text Code

Transformed Output

Character Length 77 Chars
Calculated Payload 62 Bytes
Execution Sandbox 100% Client-Side

Binary-to-Text Encoding: basE91 Specifications, PDF Streams, and the Architecture of Base91 Handlers

In back-end network transmissions, data streaming protocols, and legacy PDF compilation frameworks, conveying raw binary data streams through standard text-only gateways presents unique serialization challenges. While Base64 remains common, it adds a bulky 33% payload size overhead. By utilizing an automated Base91 (basE91) Encoder & Decoder, developers can transmit binary streams with an ultra-efficient 25% overhead.

What is Base91 (basE91)?

basE91 is an optimized binary-to-text encoding algorithm designed by Joachim Henke. It represents binary payload data using an alphabet of 91 printable characters. Compared to other encoding schemas, it is significantly more compact:

  • The Characters Spectrum: Maps values across 91 distinct printable ASCII characters—specifically excluding the backslash \, single quote ', and double quote " to optimize compatibilities in JSON and code strings.
  • Dynamic Bit Windowing: Integrates variable-length 13-bit and 14-bit data chunk splits on the fly, yielding optimal payload sizes without padded characters.
  • Efficiency Limits: Cuts payload overhead from Base64's heavy 33% down to only 23%–25%, optimizing network payloads for speed and bandwidth.

The Mathematics of 13-Bit and 14-Bit Window Splits

The mathematical conversion process operates on bit buffers. Instead of standard fixed-width splits, basE91 reads data dynamically.

Every chunk is processed by extracting a value ($V$) from the bit queue. If the extracted 13-bit value is greater than 88, the window splits at 13 bits; otherwise, it splits at 14 bits ($V < 16384$), dividing the value by 91 to yield two base-91 characters: $$c_{\text{low}} = V \bmod 91$$ $$c_{\text{high}} = \lfloor V / 91 \rfloor$$ This smart variable-width grouping ensures maximal data packing with zero trailing pad characters.

Secure Client-Side Execution Sandbox

Uploading compiled application bundles, proprietary binary files, or raw keys to online Base91 conversion utilities introduces server tracking risks and security exploits.

Our 100% Client-Side Privacy Law guarantees that all text encoding, byte array parsing, and basE91 translation algorithms are computed entirely within your browser's private memory sandbox. No data ever leaves your device, keeping your binary and encoded payloads completely secure.

01 Cryptography Encoding Tip

Always clean trailing whitespaces before decoding basE91 strings to prevent parsing anomalies. Utilize our built-in **Save Session** utility to register your calculation parameters inside the local **History Log** for convenient, secure, offline-compatible reference retrieval.