Number Sign / Hash
Block: Basic Latin
- Symbol
- #
- Unicode
U+0023- Unicode name
- NUMBER SIGN
- Block
- Basic Latin
- Script
- Common
- Category
- Punctuation, Other
- Type
- Punctuation character
Number Sign / Hash (#) is encoded as U+0023 and has the formal Unicode name NUMBER SIGN. Unicode classifies it as Punctuation, Other in the Basic Latin block. The number sign is also commonly called hash and, in social-media use, hashtag. Separately encoded named neighbors include ＃ Fullwidth Number Sign (U+FF03); those records should be compared by name and code point rather than merged because their shapes or terminology are related.
Why # Is a Distinct Typographic Character
# is Number Sign / Hash (U+0023), classified by Unicode as Punctuation, Other. In digital typography, that encoded identity is separate from the font drawing: a typeface can change width, stroke, or placement without turning the character into another code point.
This matters when punctuation, currency, or measurement marks have close visual neighbors. Preserve the intended character first; language- or style-guide spacing rules can then be applied without silently substituting a different mark.
If your character differs from this one, try what is this character #? to find the exact mark from pasted text, Unicode, or visual clues.
How # Is Used in Context
The number sign is also commonly called hash and, in social-media use, hashtag.
Do Not Collapse Number Sign / Hash Into Nearby Named Variants
Unicode stores # as U+0023, while nearby records include ＃ Fullwidth Number Sign (U+FF03). These are separate encoded identities, not alternate font drawings of one character.
The comparison is useful because a shared word in the name, a mirrored direction, or a similar outline can make two symbols appear interchangeable. When the distinction matters, compare the complete Unicode name and code point before replacing one record with another.
Why Number Sign / Hash Can Look Different Across Platforms
Unicode defines the character or sequence, but the visual artwork comes from the font, emoji set, and rendering system. As a result, shape, color, proportions, and detail can vary without changing the encoded identity.
For identification, compare code points and sequence data rather than expecting pixel-for-pixel consistency. This is especially important for emoji and symbols whose presentation is highly stylized by platforms.
How # Is Encoded
U+0023 = decimal 35 = HTML # / #. A Unicode escape-style form is u0023. Its UTF-8 bytes are 23.
Use these identifiers in markup, source code, exports, or character diagnostics when the glyph alone is not enough.
Check the Code Point Before Replacing #
This character is linked with nearby or confusable records including ＃ Fullwidth Number Sign (U+FF03), ♯ Music Sharp Sign (U+266F), and 井 Cjk Unified Ideograph-4E95 (U+4E95). The relationship is useful for identification, but it does not make those characters interchangeable.
Fonts can reduce or exaggerate visual differences, so use each character's Unicode value and name when the distinction matters. Replacing one code point with another can change meaning, search behavior, parsing, sorting, or typography even when the glyphs appear close on screen.