What Is Glitch Text? Zalgo Text Explained

What is glitch text?

Glitch text — also called Zalgo text — is text that appears corrupted, overflowing, or covered in stacked marks above and below the letters. It looks like a rendering error or a horror movie effect. Here is the same word at three intensity levels:

It is not a rendering error. Every character in glitch text is intentional, valid Unicode. The visual effect is created by stacking Unicode combining diacritical marks on top of and below each letter.

How glitch text works — combining diacritical marks

Unicode includes a range of combining diacritical marks — characters like accents, tildes, and dots that attach to the preceding character rather than taking up their own space. The letter é is the letter e followed by a combining acute accent (U+0301). Most languages use one or two combining marks per character.

Glitch text works by stacking many combining marks on a single base character — sometimes dozens. The Unicode standard does not set a hard limit on how many combining marks can follow a character, so text renderers simply draw them all, one on top of another, creating the overflowing tower effect.

The combining marks used in glitch text come primarily from two Unicode blocks:

• Combining Diacritical Marks (U+0300–U+036F): 112 combining characters including grave, acute, circumflex, tilde, diaeresis, macron, and many others. These typically appear above the base character.
• Combining Diacritical Marks Below (U+0316–U+0333): Marks that attach below the character — cedilla, ogonek, combining rings, and underscores — responsible for the text that hangs below the baseline.

The intensity of the glitch effect is controlled by how many combining marks are stacked per character. Low intensity adds 2–5 marks. High intensity can add 50–100+, creating text that overflows far outside its normal line boundaries.

Where glitch text comes from — the Zalgo origin

The term Zalgo comes from an internet meme that originated around 2004–2006 in early internet forums. The name refers to a fictional cosmic horror entity — a creature associated with madness, corruption, and the breakdown of reality. Corrupted, overflowing text became the visual representation of this entity in creepypasta culture.

The text effect itself predates the meme — Unicode combining marks have existed since the Unicode 1.0 standard in 1991. But the deliberate stacking of marks to create a horror aesthetic was popularized by the Zalgo meme, which is why the effect is still called “Zalgo text” in many generators and communities.

Today the aesthetic has spread well beyond its horror origins and is used in gaming communities, social media posts, art projects, UI design for dark or glitch aesthetics, and anywhere that “corrupted” text communicates the right visual mood.

Where glitch text works — and where it breaks

Because glitch text is valid Unicode, it pastes into most text fields correctly. But some platforms and applications handle it unexpectedly.

• Social media (Twitter/X, Instagram, TikTok): Works. The combining marks render as intended and the text displays with the full glitch effect.
• Discord: Works, though very high-intensity Zalgo text may be filtered in servers that have moderation bots configured to strip it.
• Some databases and APIs: Systems that normalize Unicode input (such as NFC or NFKC normalization) may strip combining marks, removing the glitch effect entirely.
• Screen readers: Each combining mark may be announced individually or as a character sequence. High-intensity glitch text is inaccessible and should never be used in content that needs to be read aloud.
• PDF and print: Renders correctly in most PDF viewers but may cause layout overflow issues in containers with fixed line heights.