ASCII Converter
Convert text to ASCII decimal, hexadecimal, binary, and octal codes, or decode ASCII codes back to characters. Limited to standard ASCII (0-127) - non-ASCII characters are flagged, not silently mislabeled.
About ASCII
ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns each letter, digit, punctuation mark, and control signal a number from 0 to 127. Codes 32-126 are printable; 0-31 and 127 are control characters that were originally used to operate hardware like teletypes and printers.
ASCII Character Sets
Control Characters (0-31, 127)
- • 0: NUL (null character)
- • 7: BEL (bell/alert)
- • 8: BS (backspace)
- • 9: TAB (horizontal tab)
- • 10: LF (line feed/newline)
- • 13: CR (carriage return)
- • 27: ESC (escape)
- • 127: DEL (delete)
Printable Characters (32-126)
- • 32: Space
- • 33-47: Punctuation (!@#$%)
- • 48-57: Digits (0-9)
- • 65-90: Uppercase (A-Z)
- • 97-122: Lowercase (a-z)
- • 123-126: Symbols ({|}~)
Full ASCII Table (0-127)
Every standard ASCII code, decimal and hex, with control codes shown in brackets.
| Dec | Hex | Char | Dec | Hex | Char | Dec | Hex | Char | Dec | Hex | Char |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 00 | [NUL] | 32 | 20 | [Space] | 64 | 40 | @ | 96 | 60 | ` |
| 1 | 01 | [SOH] | 33 | 21 | ! | 65 | 41 | A | 97 | 61 | a |
| 2 | 02 | [STX] | 34 | 22 | " | 66 | 42 | B | 98 | 62 | b |
| 3 | 03 | [ETX] | 35 | 23 | # | 67 | 43 | C | 99 | 63 | c |
| 4 | 04 | [EOT] | 36 | 24 | $ | 68 | 44 | D | 100 | 64 | d |
| 5 | 05 | [ENQ] | 37 | 25 | % | 69 | 45 | E | 101 | 65 | e |
| 6 | 06 | [ACK] | 38 | 26 | & | 70 | 46 | F | 102 | 66 | f |
| 7 | 07 | [BEL] | 39 | 27 | ' | 71 | 47 | G | 103 | 67 | g |
| 8 | 08 | [BS] | 40 | 28 | ( | 72 | 48 | H | 104 | 68 | h |
| 9 | 09 | [TAB] | 41 | 29 | ) | 73 | 49 | I | 105 | 69 | i |
| 10 | 0A | [LF] | 42 | 2A | * | 74 | 4A | J | 106 | 6A | j |
| 11 | 0B | [VT] | 43 | 2B | + | 75 | 4B | K | 107 | 6B | k |
| 12 | 0C | [FF] | 44 | 2C | , | 76 | 4C | L | 108 | 6C | l |
| 13 | 0D | [CR] | 45 | 2D | - | 77 | 4D | M | 109 | 6D | m |
| 14 | 0E | [SO] | 46 | 2E | . | 78 | 4E | N | 110 | 6E | n |
| 15 | 0F | [SI] | 47 | 2F | / | 79 | 4F | O | 111 | 6F | o |
| 16 | 10 | [DLE] | 48 | 30 | 0 | 80 | 50 | P | 112 | 70 | p |
| 17 | 11 | [DC1] | 49 | 31 | 1 | 81 | 51 | Q | 113 | 71 | q |
| 18 | 12 | [DC2] | 50 | 32 | 2 | 82 | 52 | R | 114 | 72 | r |
| 19 | 13 | [DC3] | 51 | 33 | 3 | 83 | 53 | S | 115 | 73 | s |
| 20 | 14 | [DC4] | 52 | 34 | 4 | 84 | 54 | T | 116 | 74 | t |
| 21 | 15 | [NAK] | 53 | 35 | 5 | 85 | 55 | U | 117 | 75 | u |
| 22 | 16 | [SYN] | 54 | 36 | 6 | 86 | 56 | V | 118 | 76 | v |
| 23 | 17 | [ETB] | 55 | 37 | 7 | 87 | 57 | W | 119 | 77 | w |
| 24 | 18 | [CAN] | 56 | 38 | 8 | 88 | 58 | X | 120 | 78 | x |
| 25 | 19 | [EM] | 57 | 39 | 9 | 89 | 59 | Y | 121 | 79 | y |
| 26 | 1A | [SUB] | 58 | 3A | : | 90 | 5A | Z | 122 | 7A | z |
| 27 | 1B | [ESC] | 59 | 3B | ; | 91 | 5B | [ | 123 | 7B | { |
| 28 | 1C | [FS] | 60 | 3C | < | 92 | 5C | \ | 124 | 7C | | |
| 29 | 1D | [GS] | 61 | 3D | = | 93 | 5D | ] | 125 | 7D | } |
| 30 | 1E | [RS] | 62 | 3E | > | 94 | 5E | ^ | 126 | 7E | ~ |
| 31 | 1F | [US] | 63 | 3F | ? | 95 | 5F | _ | 127 | 7F | [DEL] |
ASCII vs Unicode
| Feature | ASCII | Unicode (UTF-8) |
|---|---|---|
| Character Count | 128 (7-bit, codes 0-127) | Over 140,000 characters |
| Language Support | English only | All world languages |
| Emoji Support | No | Yes |
| Size | 1 byte per character | 1-4 bytes per character |
| Compatibility | Universal legacy support | Backward compatible with ASCII |
This converter works character by character, mapping each one to its standard ASCII code point (0-127) and flagging anything outside that range. If you need byte-level UTF-8 encoding instead - translating whole text into 8-bit binary and back, including accented letters and emoji - the Binary Translator is built specifically for that. For other number-base conversions, see the Hex Converter and Decimal to Binary tools.
Common Use Cases
- •Data Transmission: Sending text data between systems
- •File Formats: CSV, TXT, and plain text files
- •Programming: Character manipulation and string processing
- •Debugging: Inspecting character codes in data
- •Protocols: HTTP, SMTP, and FTP headers use ASCII
- •Sorting: Alphabetical ordering based on ASCII values
Interesting ASCII Facts
Case Conversion Trick
To convert between uppercase and lowercase, flip the 6th bit (add or subtract 32). For example: 'A' (65) + 32 = 'a' (97). This works because uppercase and lowercase letters are placed exactly 32 positions apart.
Digit to Number Conversion
To convert the character '5' to the number 5, subtract 48 (the ASCII code of '0'): '5' (53) - 48 = 5. This pattern works for all digits 0-9.
Historical Origin
ASCII was standardized in the 1960s for teletype machines. Code 127 (DEL) was designed to erase mistakes on paper tape by punching every hole in a column.
Frequently Asked Questions
What is the difference between ASCII and UTF-8?
ASCII is a 7-bit standard that encodes 128 characters (codes 0-127). UTF-8 is a variable-length Unicode encoding that represents well over 140,000 characters, including emoji and non-Latin scripts, while staying byte-compatible with ASCII for codes 0-127.
Why do printable ASCII characters start at code 32?
Codes 0-31 (plus 127) are reserved for control characters such as tab, line feed, and escape. Code 32 is the first printable character: a space.
Can ASCII represent accented letters, emoji, or non-Latin scripts?
No. Standard ASCII only covers codes 0-127, which is enough for unaccented English letters, digits, and basic punctuation. Characters like e with an accent, the euro sign, Chinese characters, or emoji require Unicode encodings such as UTF-8. This converter flags any character outside 0-127 instead of mislabeling it as ASCII.
What is 'extended ASCII', and does this converter support it?
Extended ASCII refers to various 8-bit character sets (codes 128-255) such as ISO-8859-1 or Windows-1252. There is no single universal standard for this range - the mapping depends on the code page in use. This converter only processes standard ASCII (0-127) so results stay unambiguous.
Why is the space character code 32?
Code 32 sits exactly 32 positions before the uppercase letters, which start at 65. That gap is what makes the uppercase/lowercase conversion trick (plus or minus 32) work. It was a deliberate choice in the original ASCII standard.
Popular Ways to Use This Tool
Explore focused ASCII converter guides for common use cases.
ASCII converter for text to ASCII
For developer utilities
ASCII to text converter for students
For computer science assignments
ASCII converter for PHP developers
For PHP string debugging
ASCII code converter for JavaScript
For JavaScript text processing
ASCII converter for URL debugging
For URL and query string checks
ASCII table converter for beginners
For programming tutorials
Related Tools
You might also find these tools useful
Binary Converter
Convert text, UTF-8 bytes, and binary values without focusing only on readable messages.
Binary Calculator
Add, subtract, multiply, and divide binary numbers for math and computer science exercises.
Binary to Decimal
Turn base-2 numbers into decimal values for programming, networking, and study notes.
Binary to HEX
Compress long binary strings into hexadecimal groups for code, memory, and color checks.
Decimal to Binary
Convert everyday base-10 numbers into binary with clear fixed-width output.
Decimal to HEX
Translate decimal values into compact hexadecimal notation for technical references.