Free Online ASCII Encoder & Decoder
Convert text to ASCII decimal codes and back. View character-to-code mappings with configurable output formats.
text_fields Input
code ASCII Output
| Character | ASCII Code |
|---|---|
| Enter text and click Encode to see mapping | |
Key Features
Instant Processing
All operations run locally in your browser for instant, zero-latency results.
Privacy Protected
Your data never leaves your browser. No server storage or tracking.
Frequently Asked Questions
Basics
What is the difference between ASCII and UTF-8?
ASCII defines 128 characters using 7 bits (0-127), covering English letters, digits, and basic punctuation. UTF-8 is a superset that extends to millions of code points using multi-byte sequences. This tool handles the standard 7-bit ASCII range (0-127).
Why does the letter A map to 65 and not 1?
The ASCII standard was defined in 1963 with a specific layout. Uppercase A was placed at position 65 (0x41) so that flipping bit 6 turns uppercase into lowercase (A=65, a=97; difference is exactly 32). Codes 0-31 were reserved for control characters.
Usage Tips
What output delimiter should I use for my programming language?
Use Space Separated for general readability. Use Comma Separated for CSV import or JavaScript arrays. Use Array Format for directly pasting into C, Java, or Go code as an initialized integer array.
Does this tool handle extended ASCII (128-255)?
No, this tool operates on standard 7-bit ASCII (0-127). The range 128-255 belongs to various extended ASCII schemes. For characters beyond 0-127, use the Unicode Converter or Hex Encoder/Decoder instead.