Encode & Decode Tools
Encoding problems are some of the most confusing bugs on the web: a query string that breaks because of an unescaped ampersand, an image that needs to be embedded as a data URI, or an authentication token whose claims you just want to read. This collection gathers the encoders and decoders developers reach for most often into one place.
Base64 and Image to Base64 convert text, files and images to and from Base64 data URIs. The URL Encoder percent-encodes components or full URLs, and the HTML Entity tool escapes characters like < and & for safe markup. The JWT Decoder reveals a token's header and payload with exp and iat shown as readable dates, and the Hash Generator computes MD5, SHA-1 and SHA-256/384/512 digests as you type. For lower-level work, the Binary / Hex Encoder converts text to binary, hex, octal or ASCII codes, and the Morse Code Translator handles dots and dashes with audio playback.
Each tool works both ways where it makes sense and runs entirely in your browser, so tokens, secrets and private files never leave your device.
All Encoders & Decoders (8)
Base64 Encoder/Decoder
Encode and decode Base64 text.
Open tool →URL Encoder/Decoder
Percent-encode and decode URLs.
Open tool →JWT Decoder
Decode JSON Web Token header and payload.
Open tool →Hash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes.
Open tool →HTML Entity Encoder
Encode and decode HTML entities.
Open tool →Image to Base64
Convert images to Base64 data URIs.
Open tool →Binary / Hex Encoder
Convert text to binary, hex, octal or ASCII.
Open tool →Morse Code Translator
Translate text to and from Morse code.
Open tool →Frequently Asked Questions
What is the difference between encoding, hashing and encryption?↓
Encoding (Base64, URL encoding, HTML entities) changes the representation of data so it can be transported safely and is fully reversible without a key. Hashing (MD5, SHA-256) produces a fixed-length fingerprint that cannot be reversed. Encryption scrambles data so it can only be read with a key. Base64 is not encryption.
Is it safe to decode a JWT online?↓
With NJHTools, yes — the JWT Decoder runs locally in your browser and never uploads the token. Decoding only reads the header and payload; it does not verify the signature.
When should I use URL encoding instead of Base64?↓
Use URL (percent) encoding to safely place text inside a URL or query string. Use Base64 to represent binary data such as images or files as plain text, for example in data URIs, JSON payloads or email.
Can these tools decode as well as encode?↓
Yes. Base64, URL, HTML entity, binary/hex and Morse code tools work in both directions. Hashes are one-way by design, so the Hash Generator only generates digests.
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