Vietnamese tone marks are diacritical marks placed above or below vowels to indicate the tone of a word. Vietnamese is a tonal language with 6 distinct tones (including the level tone which has no mark). The tone marks are: sắc (acute accent, e.g., á), huyền (grave accent, e.g., à), hỏi (hook above, e.g., ả), ngã (tilde, e.g., ã), and nặng (dot below, e.g., ạ). The level tone (ngang) uses no diacritical mark.

Vietnamese has 6 tones: Ngang (level/neutral, no mark), Sắc (sharp/rising, acute accent), Huyền (falling, grave accent), Hỏi (dipping-rising, hook above), Ngã (broken/creaky rising, tilde), and Nặng (heavy/dropping, dot below). Each tone can completely change the meaning of a word. For example, "ma" (ghost), "má" (mother/cheek), "mà" (but), "mả" (tomb), "mã" (code/horse), and "mạ" (rice seedling) all have different meanings.

There are several common reasons to remove Vietnamese tone marks: 1) Creating SEO-friendly URLs (slugs) from Vietnamese titles, 2) Generating filenames that work reliably across different systems, 3) Simplifying text for search engines or databases that don't handle diacritics well, 4) Creating ASCII-compatible versions of Vietnamese text for legacy systems, 5) Helping Vietnamese language learners focus on pronunciation by comparing tonal and non-tonal versions side by side.

The "Add Tone Marks" feature allows you to apply a selected tone to all eligible vowels in your text. First, the tool removes any existing tone marks, then it applies your chosen tone (Sắc, Huyền, Hỏi, Ngã, or Nặng) to all base vowels (a, ă, â, e, ê, i, o, ô, ơ, u, ư, y). For vowel clusters (like "ao", "ai", "ua"), the tone is placed on the first vowel of the cluster following standard Vietnamese orthography rules. The "Ngang" (level) option effectively removes all tones. Note: for complex multisyllabic text, professional Vietnamese input methods may provide more nuanced results.

Yes! The Vietnamese Tone Converter fully supports both uppercase and lowercase letters. All tone-bearing uppercase vowels like Á, À, Ả, Ã, Ạ, Ắ, Ằ, Ẳ, Ẵ, Ặ, Ấ, Ầ, Ẩ, Ẫ, Ậ, É, È, Ẻ, Ẽ, Ẹ, Ế, Ề, Ể, Ễ, Ệ, and their counterparts for other vowels are all correctly converted. This makes the tool suitable for processing titles, headings, and all-caps Vietnamese text.

Besides the 5 tone marks, Vietnamese uses several base letters with diacritics that are considered distinct letters of the alphabet: Ă/ă (a with breve), Â/â (a with circumflex), Ê/ê (e with circumflex), Ô/ô (o with circumflex), Ơ/ơ (o with horn), Ư/ư (u with horn), and Đ/đ (d with stroke). These are NOT tone marks—they are separate letters. When removing tone marks, these base diacritics are preserved. For example, "đường" becomes "đuong" (not "duong"), and "tiếng" becomes "tieng" (not "ting").

Absolutely! This Vietnamese Tone Converter is completely free to use online. There are no usage limits, no registration required, and no ads cluttering your experience. You can convert as much text as you need, whenever you need it. The tool runs entirely in your browser for maximum privacy—your text never leaves your device.

In Vietnamese, "có dấu" means "with marks"—referring to text that includes all the tone diacritics (sắc, huyền, hỏi, ngã, nặng). "Không dấu" means "without marks"—text where all tone marks have been removed, leaving only the base letters. For example, "Tiếng Việt" (có dấu) becomes "Tieng Viet" (không dấu). Many Vietnamese speakers use không dấu text in informal digital communication, SMS, or when using systems that don't support Vietnamese input methods.