Use the free Underline Text Generator below: your data never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
What underlined text with Unicode means
Most apps give you an underline button, but the underline disappears the moment you copy the text somewhere else — into a bio, a comment, a chat message or a plain-text field. Unicode underlining solves that: a combining underline mark is attached to every character, so the line underneath travels with the text itself. The underlined words stay underlined wherever plain text goes, because the underline is part of the characters, not formatting applied on top of them.
This generator adds the combining low line after each letter, and optionally a double low line for a heavier double underline. The result looks like classic underlined handwriting or typewriter emphasis, and it works in usernames, posts, messages and documents that do not support rich formatting. It is emphasis that cannot be stripped by pasting.
How the underline is built
The tool uses combining characters, marks that join onto the previous character instead of occupying their own space. The single underline uses the combining low line, and the double underline uses the combining double low line. By default spaces are skipped, so the underline breaks naturally between words like a normal underline under text; turn that option off and even the spaces get underlined, producing one continuous line under the whole phrase.
Everything runs in your browser and the conversion is instant. Type your phrase, pick single or double, and copy the result. There is no image to download and no font to install, and the underlined text remains searchable and selectable as text — screen readers and search boxes still see the underlying letters, with the marks attached.
Where underlined text is useful
Underlining is the oldest emphasis in writing, older than bold and italics, and it still signals “pay attention to this” more plainly than any other style. Use it for the key phrase in a post, a deadline in a message, a title in a bio, or the answer in a quiz. In places where bold and italics are unavailable — many comment systems, game chats, plain-text emails — an underline is often the only emphasis you have, and it stands out precisely because everything else is flat.
It also helps with structure. Underlined headings divide a long caption into sections without needing real heading formatting, and underlined labels make form-like posts (“Name:”, “Date:”, “Price:”) easier to scan. Teachers use underlined text for fill-in-the-blank style worksheets, and sellers use it to underline prices, offers and calls to action in listings where formatting buttons do not exist.
Tips for underlines that look good
Keep underlined runs short. A word or a short phrase underlined reads as emphasis; a whole paragraph underlined reads as a wall of lines and loses its power. Single underline is the safe default — it matches what readers expect from handwriting and typewriters. Double underline is stronger and rarer, so save it for the single most important line, like a title or a final warning, where extra weight is genuinely warranted.
Check the result on the device your audience uses. Combining underlines render well on modern phones and browsers, but very long underlined lines can wrap in ways that look slightly uneven, and some older systems draw the line a little lower than usual. Test with your actual phrase, at the actual size, before you publish it as a permanent name or title. And keep a plain copy of your phrase, because if a platform strips combining marks, you will want to re-underline in seconds.
Underline versus strikethrough and other marks
Underline and strikethrough are mirror images: one adds a line below, the other a line through. Underline means emphasis or importance; strikethrough means correction, a joke, or a crossed-out old price. They come from the same combining-mark technique, and they can even be combined — though a word that is both underlined and struck through is usually too busy to read. Compared with bold-style Unicode alphabets, underlining keeps your letters in their familiar shapes, so it is the most readable emphasis of all: the words stay normal, and only the line underneath does the talking.