Text ↔ ASCII Converter
Interactive ASCII Table (32–126)
Click any character to insert it into the text input.
Common ASCII Codes
| Character | Decimal | Hex | Description |
|---|---|---|---|
| A | 65 | 0x41 | Uppercase A |
| Z | 90 | 0x5A | Uppercase Z |
| a | 97 | 0x61 | Lowercase a |
| z | 122 | 0x7A | Lowercase z |
| 0 | 48 | 0x30 | Digit zero |
| 9 | 57 | 0x39 | Digit nine |
| (space) | 32 | 0x20 | Space character |
| ! | 33 | 0x21 | Exclamation mark |
| @ | 64 | 0x40 | At sign |
| \n | 10 | 0x0A | Line feed (newline) |
What Is ASCII?
ASCII (American Standard Code for Information Interchange) is a character encoding standard that maps 128 characters to decimal numbers 0 through 127. It was first published in 1963 and remains the foundation of nearly all modern text encoding.
The 128 ASCII characters include:
- Control characters (0–31, 127) — non-printable codes like newline (10), tab (9), and carriage return (13)
- Printable characters (32–126) — letters, digits, punctuation, and the space character
How ASCII Decimal Conversion Works
Every character has a fixed decimal number. To convert text to ASCII, you replace each character with its assigned code. To convert back, you look up each number and output the matching character.
Example: The word Cat becomes 67 97 116 — where C=67, a=97, t=116.
ASCII vs Unicode
ASCII covers only 128 characters — enough for English text, digits, and basic punctuation. Unicode is a superset that extends this to over 149,000 characters, covering virtually every writing system, mathematical symbol, and emoji. The first 128 Unicode code points (U+0000 to U+007F) are identical to ASCII, so ASCII is fully compatible with Unicode.
When ASCII Codes Are Useful
- Debugging — identifying hidden or unexpected characters in strings
- Programming — character comparison, validation, and encoding logic
- Data transmission — understanding how protocols encode text
- Education — learning how computers represent text internally
- Puzzles and CTFs — decoding messages stored as decimal sequences
Limitations
- Standard ASCII only covers codes 0–127 (English characters and basic symbols)
- Characters like é, ñ, or 日 are not part of ASCII — they require Unicode encoding
- This tool uses Unicode code points for characters beyond ASCII, which means it works for any character but the output codes above 127 are Unicode, not strictly ASCII
Related Tools
- ASCII Table — look up any ASCII code by character, decimal, or hex value
- Text to Binary Converter — convert text to binary representation
- Binary Text Decoder — decode binary sequences back to readable text
- Hex to Text Decoder — convert hexadecimal values to text
- Unicode Codepoint Decoder — look up Unicode code points for any character
Privacy & Limitations
- All calculations run entirely in your browser -- nothing is sent to any server.
- Results are computed locally and should be verified for critical applications.
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ASCII Decimal Converter FAQ
What is ASCII?
ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns a unique number (0–127) to each character, including letters, digits, punctuation, and control characters. For example, uppercase 'A' is 65, lowercase 'a' is 97, and the digit '0' is 48.
How do I convert text to ASCII decimal codes?
Each character in your text has a corresponding ASCII decimal number. To convert, look up each character's code: A=65, B=66, a=97, b=98, 0=48, space=32, and so on. This tool does the lookup automatically — paste your text and click 'Text → ASCII'.
How do I convert ASCII decimal codes back to text?
Enter the decimal codes separated by spaces (e.g., '72 101 108 108 111') and click 'ASCII → Text'. Each number is mapped back to its corresponding character. 72 is 'H', 101 is 'e', and so on — producing 'Hello'.
What is the difference between ASCII and Unicode?
ASCII covers 128 characters (codes 0–127) and only includes English letters, digits, and basic punctuation. Unicode is a superset that covers over 149,000 characters from virtually every writing system, including emoji. The first 128 Unicode code points are identical to ASCII.
What ASCII code is the space character?
The space character has ASCII decimal code 32. It is the first printable character in the ASCII table (codes 0–31 are non-printable control characters).
Can this tool handle characters outside the ASCII range?
Yes. While standard ASCII only covers codes 0–127, this converter supports the full Unicode range (up to 1,114,111). Characters like accented letters, emoji, and symbols outside basic ASCII are converted using their Unicode code point values.
Is my data sent to a server?
No. All conversion happens in your browser using JavaScript. No text or codes are transmitted to any server.
What separator does the tool use between ASCII codes?
The tool outputs ASCII codes separated by spaces. When decoding, it accepts any whitespace (spaces, tabs, newlines) as separators between codes.