How combining marks create Zalgo text
Unicode combining marks were designed to attach accents, pronunciation signs, and other modifiers to a base character. They normally appear in small, meaningful combinations. Zalgo text creates a visual glitch by attaching several marks to each ordinary letter, often mixing marks that extend above and below the normal line. The base phrase is still present, but the stacked modifiers make it look corrupted or unstable. Nothing is being drawn as an image, so the result can still be copied as text when the destination accepts those Unicode code points.
Different fonts and layout engines position combining marks in different ways. One browser may stack them neatly while another lets them collide with neighboring lines. Fixed-height inputs can clip the top or bottom, and some apps normalize or remove unusual sequences. This generator starts from cleaned base text and caps the available intensity, which makes the output more predictable than adding marks without a limit. Even so, the target platform controls the final rendering, so a successful preview cannot guarantee identical spacing everywhere.