＿ Underline Text Generator
By ToolNimba Text Team · Updated 2026-06-19
Type some text above to see every underlined style.
An underline text generator turns ordinary words into underlined text you can paste anywhere, even in apps that have no formatting buttons at all. It works by adding an invisible Unicode combining mark after each letter, so the line is baked into the characters themselves rather than stored as styling. Type or paste your text, and this tool instantly produces a single underline, a double underline and an underlined strikethrough version, each with its own copy button. Because the result is plain text and not a special font, you can drop it straight into Instagram, Twitter or X, TikTok, Discord, WhatsApp, a username field or a Google Doc and the line stays put.
What is the Underline Text Generator?
Unicode includes a family of "combining" characters built to attach to the character that comes just before them. A normal letter occupies one slot on screen, but a combining mark has zero width: instead of sitting beside its neighbour, it renders on top of or underneath it. The underline generator walks through your text one character at a time and inserts a combining low line immediately after each one. The browser then draws the letter and the line as a single combined glyph, so "hello" becomes underlined letter by letter.
Three styles do the work here. U+0332 (combining low line) draws a single line under each character, the standard underline. U+0333 (combining double low line) draws two stacked lines for a double-underline emphasis often used for headings or totals. Combining U+0332 with U+0336 (combining long stroke overlay) places a line both under and through the character at once, giving an underlined strikethrough look. The marks are added to spaces and punctuation as well, so the underline runs unbroken across whole words and sentences instead of stopping at each gap.
The real advantage of this method is portability. A normal underline produced by the U button in a word processor is rich-text styling, and that styling is stripped away the instant you copy the text into a plain box such as a tweet, a chat message or a bio field. Combining marks are part of the text string itself, so they survive copying and pasting into almost any field. The trade-off is that combining marks are not always announced cleanly by screen readers, and a handful of older fonts position the line slightly off, so reach for underlined Unicode text as a visual flourish rather than for content that must be fully accessible.
When to use it
- Underlining a name, title or key phrase in a bio or profile where the app offers no formatting.
- Adding emphasis to a word in a chat, comment or post on platforms like Discord, WhatsApp or X.
- Creating an underlined strikethrough to show a corrected or replaced word in a playful way.
- Styling headings or totals with a double underline in usernames, captions and short posts.
How to use the Underline Text Generator
- Type or paste the text you want to underline into the box.
- Look at the single underline, double underline and underlined strikethrough versions generated below.
- Pick the style you like and press its Copy button.
- Paste the underlined text into your chat, bio, caption, document or post.
Formula & method
Worked examples
You want a single underline on the word "Sale".
- Take each letter in turn: S, a, l, e.
- After every letter, insert U+0332 (combining low line).
- S becomes S̲, a becomes a̲, l becomes l̲, e becomes e̲.
- Join them back together in order.
Result: S̲a̲l̲e̲
You want an underlined strikethrough on the word "old".
- Take each letter: o, l, d.
- After every letter, insert U+0336 (long stroke overlay) then U+0332 (low line).
- o becomes o̶̲, l becomes l̶̲, d becomes d̶̲.
- Join them in order to get a word that is both struck through and underlined.
Result: o̶̲l̶̲d̶̲
Combining marks used by each underline style
| Style | Unicode mark | Code point | Effect |
|---|---|---|---|
| Single underline | combining low line | U+0332 | One line under each character |
| Double underline | combining double low line | U+0333 | Two stacked lines under each character |
| Underlined strikethrough | long stroke overlay + low line | U+0336 + U+0332 | A line through and under each character |
Where Unicode underlined text usually pastes correctly
| Place | Works |
|---|---|
| Instagram bio and captions | Yes |
| Twitter / X posts | Yes |
| Discord and WhatsApp messages | Yes |
| TikTok bio and comments | Yes |
| Plain username fields | Usually, if the field allows special characters |
Common mistakes to avoid
- Expecting it to work like a font change. This tool does not pick a new typeface. It adds a combining line to ordinary letters, so the underline travels with the text as plain characters rather than as formatting that can be turned off later.
- Using underlined Unicode for important accessibility content. Screen readers may read combining marks awkwardly or skip them, so do not rely on underlined Unicode text for content that must be read aloud clearly. Use it for visual effect only.
- Assuming every field accepts it. Some username and form fields reject special characters or strip combining marks. If your underline disappears after submitting, the field only allows basic letters and numbers.
- Worrying when the line sits slightly off. A few older fonts position combining marks imperfectly, so the underline may look a touch high or uneven. The text is still correct; only the on-screen rendering varies by font.
Glossary
- Combining mark
- A zero-width Unicode character that attaches to the character before it, rendering over or under it instead of beside it.
- Combining low line
- The mark U+0332 that draws a single underline under the preceding character.
- Combining double low line
- The mark U+0333 that draws two stacked lines under the preceding character for a double underline.
- Code point
- The unique number, written as U+ followed by hex digits, that identifies a character in the Unicode standard.
- Plain text
- Text stored as characters only, with no separate styling layer, which is what lets the underline survive copy and paste.
Frequently asked questions
How does an underline text generator work?
It adds a Unicode combining low line (U+0332) after every character in your text. That mark renders as a line directly under the character, so the underline becomes part of the text itself and is not separate formatting that can be stripped away.
Will the underline survive copy and paste?
Usually yes. Because the underline is made of combining marks inside the text string, it pastes correctly into most chats, bios, captions and posts. Some strict username or form fields reject special characters and may remove it.
What is the difference between this and the underline button in a word processor?
A word processor stores the underline as rich-text styling, which is removed when you copy into a plain box like a tweet or chat. This tool bakes the line into the characters, so it works in places that have no formatting buttons.
Can I make a double underline?
Yes. The double underline style uses U+0333 (combining double low line), which stacks two lines under each character. It is handy for headings or totals where a single line does not stand out enough.
Is underlined Unicode text accessible to screen readers?
Not reliably. Screen readers can read combining marks awkwardly or skip them, so underlined Unicode text is best used as a visual effect rather than for content that must be read aloud accurately.
Does it work with emoji and accented letters?
The tool steps through your text by code point, so emoji and accented letters stay intact. A combining underline is still added after each one, though the line may sit a little differently depending on the font.