Understand text, Unicode and byte encodings

Understand the settings

A character encoding maps text to bytes. Hexadecimal, binary and decimal display byte values in different number bases. Base64 packages bytes into printable text. These transformations are not encryption: they do not require a secret to reverse.

Unicode code points and UTF-8 bytes are different views of text. One character may take several bytes, and a visible symbol may be composed from more than one code point. A byte sequence can be valid binary data without being valid UTF-8 text.

Percent encoding is context-sensitive. This tool encodes a URL component, which means separators such as / are escaped. Encode a complete URL as one component only when that URL is itself a parameter value. A literal plus sign is not automatically treated as a space.

Step by step

1. Select the input representation and enter a small sample.
2. Read the converted outputs and any format-specific error messages.
3. Copy the representation needed by the receiving program.
4. For arbitrary binary data, verify bytes instead of assuming a readable text result must exist.

Follow one character

The text é is Unicode U+00E9, UTF-8 bytes c3 a9, and Base64 w6k=. By contrast, hexadecimal ff is a valid byte but is not valid standalone UTF-8. A text error does not make the byte representation invalid.

Limits and what to check

• Input is limited to 100,000 characters; keep large binary-file tasks in a local utility.
• No encryption, decryption, charset guessing or arbitrary-file conversion.
• Invalid byte values and malformed Unicode sequences are reported rather than silently accepted.
• Processing stays in the browser; no input is uploaded.

Troubleshooting