ASCII Table

About the ASCII table

ASCII (American Standard Code for Information Interchange) assigns a number from 0 to 127 to letters, digits, punctuation and a set of control codes. This table lists every one of those 128 values with its decimal, hexadecimal, octal and binary form, the character it represents, and a short description. The table is generated entirely in the page, so it's instantly complete and there is nothing to load or download.

Printable characters and control codes

Codes 32 to 126 are the printable characters: space, digits, uppercase and lowercase letters, and common punctuation — the everyday text you can type and see. Codes 0 to 31, plus 127, are control codes that don't print but instruct devices: LF (10) starts a new line, CR (13) returns the cursor, TAB (9) inserts a tab, and ESC (27) begins escape sequences. They date from the teleprinter era but still underpin how text and terminals work today.

How to use the table

Type into the filter box above the table to narrow the rows instantly. You can search by a decimal value like 65, a hex code like 41 or 0x41, an octal like 101, a character like A, or part of a description such as escape. The filter is case-insensitive and matches against the value, its character and its description at once, so it also works for control names like LF or DEL. Clearing the box restores the full table.

A concrete example

Say you're debugging a protocol and a log shows the byte 0x0A. Type 0a (or 10) into the filter: the table returns decimal 10, shows the hex 0A, the octal 012, the binary 00001010, the control code LF and the description "Line Feed" — a newline, not a printable space. In the same way, typing 97 isolates lowercase a, and searching escape finds the ESC control code at 27 even though it prints no glyph.

What to expect

Every row shows six columns: the decimal value from 0 to 127, its hexadecimal code (uppercase), its octal representation, its 8-digit binary form, the character or control abbreviation, and a one-line description. Printable characters display their glyph, while control codes show abbreviations such as NUL, LF, CR, SP for space and DEL for 127. The sticky header keeps the column labels visible as you scroll, hover highlighting makes rows easy to track, and everything runs locally in your browser.

Common problems and fixes

If typing a decimal like 9 doesn't seem to narrow things down, remember the filter also matches characters and descriptions, so 9 can match several rows at once — add more digits or a name to be specific. If a hex search returns nothing, make sure you're not looking for a value above 127, since this table only covers ASCII codes 0 to 127; values like 0xE9 or 233 belong to extended sets such as Latin-1, not this chart. If you type a character, note that uppercase and lowercase are case-insensitive, so A and a match different rows because they are different codes (65 versus 97) — search 97 if you specifically want lowercase. And if a row seems "blank", you're likely looking at a control code or the space character, which the table marks SP rather than a visible glyph.

Frequently asked questions