Polybius Square Cipher Tool – Online Encode & Decode
Encrypt or decrypt text using the classical 5x5 Polybius square. Excludes J or merges I/J.
UD5 Toolkit
Encrypt or decrypt text using the classical 5x5 Polybius square. Excludes J or merges I/J.
Encode or decode a string for use in a URL query parameter. See the raw and encoded versions. Dev tool.
Encode latitude/longitude into a geohash string and decode a geohash back to coordinates with precision info. Local algorithm.
Convert integers into short, unique, YouTube‑style IDs (hashids) and decode them back. Customize salt and minimum length.
Encode any file into a Base64 string that you can copy, or decode a Base64 string back to a downloadable file. Pure frontend.
Encode or decode data to/from Base58 (Bitcoin alphabet). Useful for cryptocurrency address generation testing. Fully local, no data sent.
Escape HTML special characters to prevent XSS attacks, or unescape HTML entities back to original text. Essential for web developers. Runs locally.
Instantly convert plain text into HTML‑safe escaped characters for secure display in web pages. Prevent cross‑site scripting. All processing local.
Convert your text into a string of emojis using a simple substitution cipher. Share secret messages that look fun. Decode them with the same tool. All local.
Hide your email address from scrapers by encoding it using HTML entities and CSS tricks. Still clickable for real users. Local generator.
Transform any image into a Base64 data URI for embedding directly into HTML, CSS, or JSON. Drag and drop support. Entirely browser-side conversion.
Obfuscate strings using simple techniques to prevent casual reading. Useful for hiding spoilers or email addresses from bots. Decode with the same tool.