ASCII Code Converter

Direction

ASCII Reference Table

Common control codes followed by every printable ASCII character (codes 33–126).

How to Use the ASCII Code Converter

1. 1. Choose a direction. Auto-detect decodes input that is two or more numbers from 0 to 255 separated by spaces or commas, and encodes everything else; Text → Codes and Codes → Text force a direction. A single number, or a code above 255, needs Codes → Text.
2. 2. Type or paste. Separate codes with spaces or commas. The result and a character count update as you type.
3. 3. Check the errors. A code that is not a whole number, or one above 1,114,111, is reported by name instead of being guessed at.
4. 4. Look up codes. The ASCII reference table below the tool lists the common control codes and every printable character from 33 to 126.

What ASCII Is

ASCII, the American Standard Code for Information Interchange, assigns a number from 0 to 127 to each of 128 characters, so a character fits in seven bits. The numbers fall into three groups:

Two patterns are worth knowing. A lowercase letter is its uppercase letter plus 32 (A is 65, a is 97), and the digit characters count up from 48, so 7 is 55. "Extended ASCII" is not a single standard: the 8-bit sets that fill 128–255 differ from one another. Unicode keeps the same numbers for its first 128 code points, which is why plain English text is the same in ASCII and in Unicode.

Beyond ASCII: Unicode Code Points

The converter reads text one Unicode character at a time and shows each character's code point in decimal. For ASCII text that is the ASCII code; for anything else it is the Unicode number, so é is 233 and 😀 is 128512. Decoding accepts any code up to 1,114,111 (U+10FFFF, the last Unicode code point) and builds the character from it.

A code point is not the same as a byte. The character é is one code point, 233, but two bytes in UTF-8, c3 a9. To see bytes, use Text to Hex or the Binary Code Translator.

Worked Example

72 101 108 108 111

67 97 102 233 32 128512

67 105 116 101 32 105 116  →  Cite it

The first two lines show that H is 72 and e is 101, and that the space before the emoji gets a code of its own, 32. Line feeds count too: pressing Enter in the input adds a 10.

Surprises to Avoid

• Lone numbers are treated as text. In Auto-detect, one number such as the year 2024, or a list containing a value above 255, is encoded as digits rather than decoded, so 72 gives 55 50. Choose Codes → Text to decode a single code or a Unicode code point such as 8364. A list like 10 20 30 is read as codes; choose Text → Codes if you meant digits.
• Invisible results. Codes 0–31 are control characters, so decoding 72 9 105 yields H, a tab character and i, which looks like a gap in the text.
• Surrogate codes (55296–57343) are not real characters. The tool accepts them but the output is not displayable text. Encode emoji and decode them with their full code point, such as 128512.

Which Tool Do You Need?

This page gives decimal codes and an ASCII table. For hexadecimal bytes use Text to Hex; for 8-bit groups use the Binary Code Translator; for Base64, URL and HTML encodings use the Text Encoder & Decoder. To convert a plain number between binary, octal, decimal and hex, use the Number Base Converter.

Frequently Asked Questions

How do I convert text to ASCII codes?

Type or paste the text, with the direction on Text → Codes or Auto-detect. Each character appears as its decimal code separated by spaces, so Hi becomes 72 105.

How do I convert ASCII codes back to text?

Paste decimal codes separated by spaces or commas, such as 72 101 108 108 111, with the direction on Codes → Text or Auto-detect. Each number is validated and turned back into its character.

What about characters outside the ASCII range?

They use their Unicode code point: é is 233, € is 8364 and 😀 is 128512. Any code up to 1,114,111 decodes back to a character.

What is the difference between ASCII and Unicode?

ASCII has 128 characters, numbered 0–127. Unicode contains over a hundred thousand characters from nearly all writing systems, and its first 128 numbers are identical to ASCII. Every ASCII file is therefore also valid UTF-8 text.

Why is my single code not decoded?

Auto-detect only decodes two or more numbers from 0 to 255, so a number like 2024 is encoded as the digits 2, 0, 2 and 4 (50 48 50 52). Switch the direction to Codes → Text to decode a single code or one above 255.

What is the ASCII table on this page?

A reference listing the common control codes (tab, line feed, carriage return, space) and every printable character from 33 to 126, so you can look up a code without converting.

Is my text sent to a server?

No. The conversion happens in your browser and nothing you type leaves your device.