Tilde (~): The Key, What It Means, and the Mark Over ñ

What is a tilde, and what does the ~ symbol mean?

A tilde is the small wavy line ~. It is a character of its own on every computer keyboard, and it is also the name of a mark written over letters such as ñ. Most people who look up the word mean the first one, the tilde symbol. Unicode files it as U+007E TILDE, a spacing character that stands between other characters instead of sitting on one.

Chapter 6 of the Unicode Standard (opens in a new tab) names its common jobs: alternation, an approximate value and, in some notations, logical negation. Dictionaries also use it to repeat the headword in their examples.

So a tilde meaning depends on where it stands. For most of those jobs the standard points to a more precise character, and the keyboard tilde is the stand-in that everyone can type. The table pairs each meaning with that character. The two shell rows come from POSIX (opens in a new tab), the standard behind Unix shells, and the range row from Wiktionary (opens in a new tab).

Where you see ~	What it means	The character Unicode points to	Source
in front of a number	about, roughly	∼ U+223C TILDE OPERATOR, in a formula	Unicode ch. 6, Wiktionary
a ~ b in mathematics	a is similar to b, or varies with b	∼ U+223C TILDE OPERATOR	Unicode ch. 6, NamesList
~p in logic	not p	¬ U+00AC NOT SIGN	Unicode ch. 6
in a dictionary example	the headword, repeated	⁓ U+2053 SWUNG DASH	Unicode ch. 6, Oxford
between two numbers, in East Asian text	a range, from one to the other	〜 U+301C WAVE DASH	Wiktionary, Unicode ch. 6
alone at the start of a shell path	your home directory	none: the shell reads only ~	POSIX 2.6.1
followed by a user name, as in ~root	that user's home directory	none	POSIX 2.6.1

The name came to the symbol late. Wiktionary's historical note (opens in a new tab) says dictionaries before ASCII, such as the Oxford English Dictionary of 1933, give tilde only as the accent.

The 1967 ASCII standard drew the character as a floating accent, to be printed over a letter on a paper terminal. Users took it over as a symbol, fonts changed to match, and the accent's name went with it. Unicode still allows both looks: modern fonts set ~ on the center line, while older terminal and typewriter fonts raise it like an accent.

Where is the tilde key on a US or UK keyboard?

On a US keyboard the tilde shares a key with the backtick: the first key of the number row, left of 1. Press it alone for ` and with Shift for ~. Microsoft's US keyboard layout (opens in a new tab) shows it this way. The key it calls VK_OEM_3 types U+0060 GRAVE ACCENT unshifted and U+007E TILDE with Shift.

The tilde on keyboard layouts outside the US can move. Microsoft's United Kingdom layout (opens in a new tab) puts ~ on Shift and the key that types #. With Shift, the top-left key gives ¬, the not sign, instead. That is why a "tilde key" guide written for US keyboards fails on a UK one.

A Mac follows the US pattern. We measured Apple's U.S. and ABC layouts on 2026-10-14 with UCKeyTranslate on macOS 26.6.2: Shift with the backtick key types U+007E. As a control, Shift with the 1 key typed !, as expected. Apple's Keyboard Viewer (opens in a new tab) shows the same on screen when you hold Shift.

The US International keyboard is different again. Google's Chromebook help (opens in a new tab) lists the tilde there as a dead key, pressed with Shift and the backtick key and followed by the letter. A dead key types nothing until the next key.

Keyboard	How to type ~	The same key without Shift	Source
US, Windows	Shift and the backtick key, left of 1	`	Microsoft US layout
United Kingdom, Windows	Shift and the # key	#	Microsoft UK layout
U.S. or ABC, Mac	Shift and the backtick key	`	measured, UCKeyTranslate
US International PC, Mac	Shift and the backtick key, then Space	starts a dead key: then n gives ñ	measured, UCKeyTranslate
US International, Chromebook	Shift and the backtick key, then the letter	starts the same dead key	Google Chromebook help

Why does a Mac's tilde dead key type ˜ and not ~?

Because Option+N is made for the accent, not for the symbol. Apple's page on accent marks (opens in a new tab) says so: press Option+N to enter a tilde, ˜, and then the letter, as in ã. We tested what happens when the next key is Space instead of a letter, with UCKeyTranslate on macOS 26.6.2 on 2026-10-14. On the U.S. and ABC layouts the result was U+02DC SMALL TILDE, not U+007E.

Chapter 7 of the Unicode Standard (opens in a new tab) explains why two characters exist. The old ISO 8859-1 code page left ~ unclear: an accent, or a separate symbol? Unicode uses U+007E only as a spacing character, usually drawn on the center line. It gives the raised accent standing alone a code of its own, U+02DC.

The two look alike in many fonts, and software does not treat them alike. We typed both into the shells of the same Mac on 2026-10-14:

Typed	/bin/bash 3.2.57	/bin/zsh 5.9
~/x	the home folder, then /x	the home folder, then /x
˜/x	˜/x, unchanged	˜/x, unchanged
~root	/var/root	/var/root

That is the POSIX rule at work. Only a real tilde at the start of a word becomes a home directory, so a path copied from a document that holds ˜ points nowhere. For a path, a web address or code, type Shift and the backtick key. Keep Option+N for ñ, ã and õ.

Is the ~ on the keyboard the same character as the tilde over ñ?

No. The keyboard gives U+007E, a character that takes up its own space. The tilde in ñ is U+0303 COMBINING TILDE: a mark with no width of its own, which sits on the letter before it. Unicode's names list (opens in a new tab) breaks ñ down into n and U+0303, and ã and õ into a and o with the same mark. Typing n and then the keyboard tilde gives two characters, never ñ.

We checked what normalization does to each form, with Node.js 26.0.0 (ICU 78.3, Unicode 17.0) on 2026-10-14. NFC joins a letter and its mark; NFKC also folds lookalike forms into their plain character.

Characters you have	After NFC	After NFKC
n, then U+0303	ñ, one character, U+00F1	ñ
n, then ~	still n and ~	still n and ~
˜ U+02DC	unchanged	a space and U+0303
～ U+FF5E	unchanged	~ U+007E

Several more characters share the shape. The names list and chapters 6 and 7 keep them apart:

Character	Code point	What it is for
~	U+007E TILDE	the keyboard character: paths, plain text, a rough number
◌̃	U+0303 COMBINING TILDE	the mark over a letter; IPA nasalization and a Vietnamese tone mark
˜	U+02DC SMALL TILDE	the accent standing alone, raised
∼	U+223C TILDE OPERATOR	mathematics: similar to, varies with
⁓	U+2053 SWUNG DASH	dictionaries, and alternation
〜	U+301C WAVE DASH	the JIS wave dash; for most purposes a duplicate of U+FF5E
～	U+FF5E FULLWIDTH TILDE	the wide form; NFKC turns it into ~
◌̰	U+0330 COMBINING TILDE BELOW	IPA creaky voice
◌̴	U+0334 COMBINING TILDE OVERLAY	IPA velarization or pharyngealization
◌͂	U+0342 COMBINING GREEK PERISPOMENI	a Greek accent that may be drawn like a tilde, encoded apart from U+0303

The trap runs both ways. A raised ˜ pasted after a vowel does not make ã: in the same test, a followed by U+02DC stayed a and ˜ under NFC, and NFKC turned it into a, a space and U+0303, still not ã. A combining U+0303 typed alone has nothing to sit on.

What does a tilde over a letter do, and where did the mark come from?

A tilde over a letter tells you how to say that letter, and what it says depends on the language. Oxford (opens in a new tab) defines the tilde as the mark placed over letters in some languages, and over some IPA vowels, to show how they are pronounced. Its examples are España, São Paulo and /pɒ̃ʃɒ̃/ for penchant. The usage map above shows who writes which letter. This table says what the mark does in each place:

Where	Letters	What the tilde does	Source
Spanish	ñ	makes a letter of its own, the eñe	Wiktionary
Portuguese	ã õ	marks a nasal vowel, as in anão and limões	Priberam, Wiktionary
Estonian	õ	spells a vowel of its own, /ɤ/, with no nasal sound	Wiktionary
Vietnamese	ã ẽ ĩ õ ũ ỹ, and ẫ ẵ ễ ỗ ỡ ữ	carries the tone called ngã	Unicode ch. 7, Wiktionary
IPA	any vowel	marks nasalization	NamesList, Oxford
Early Modern English	ã õ	stands for a following n or m: commãd, cõpose	Wiktionary

The Portuguese row is from Priberam (opens in a new tab), which defines til as the sign that marks nasality. The Estonian vowel and the old English spellings come from Wiktionary's entries for õ (opens in a new tab) and ã (opens in a new tab). Each letter has a fuller page: n with tilde on why Spanish counts ñ as a letter, a with accent on Portuguese ã against á, o with accent on õ, and the Vietnamese alphabet on ngã among the other tone marks.

The word itself is Spanish. Oxford dates it in English to the mid 19th century and traces it to Latin titulus, an inscription or title. Wiktionary (opens in a new tab) makes tilde a doublet of title and tittle, all from that Latin word.

Spanish still uses tilde more widely than English does. FundéuRAE (opens in a new tab) notes that Spanish calls the written accent on á a tilde, and that the wavy line of ñ is also called the virgulilla. The Spanish alphabet page covers those accent rules.

The shape began as a scribe's shortcut. Wiktionary's entry for ñ (opens in a new tab) describes a dash over a letter as medieval shorthand for an extra m or n. Early Modern English spelling used it too: commãd for command, hãmer for hammer, reckõ for reckon. Spanish kept the shortcut in ñ, where it stood for nn, and made it a letter. In most other places the line now marks a sound, not a missing letter.