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Diacritic and Tone Mark Converter

Add or convert Pinyin tone marks, strip Unicode accents, normalize text to NFC, NFD, NFKC, or NFKD, and copy a guaranteed ASCII-safe version.

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Pinyin tones · Unicode text

Convert Pinyin tones, accents, and Unicode forms

Use this converter when text is already written in Roman letters or Unicode and you need to change its notation rather than translate or romanize a source script. It can turn validated Hanyu Pinyin syllables such as ni3 and lü4 into nǐ and lǜ, convert marked Pinyin back to syllable-final tone numbers, or remove Unicode diacritics from general text. Punctuation, spacing, line breaks, and letter case stay in place unless a selected Unicode compatibility form defines a change.

The normalization mode exposes NFC, NFD, NFKC, and NFKD exactly as defined by Unicode. NFC and NFD preserve canonical equivalence; NFKC and NFKD may deliberately merge presentation or compatibility distinctions. Every result also includes a separate ASCII-safe copy. Pinyin tones become numbers and ü becomes v there; supported Latin letters are simplified, while any remaining non-ASCII character is written as an explicit Unicode escape so information is not silently discarded. Keep the original text whenever reversibility or official spelling matters.

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Only complete, validated Pinyin syllables followed by 0–5 are changed.
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Text is processed for this request only and is not saved by this tool.

How to use the converter

1. Choose the transformation

Choose a Pinyin direction, accent stripping, or exact Unicode normalization. The input is never treated as a translation request.

2. Paste and convert

The Pinyin modes validate complete syllables before changing tone notation. Other numbers and ordinary accented words remain untouched.

3. Choose the right copy

Copy the Unicode result for correct typography. Use the ASCII-safe copy only for a system that cannot accept Unicode.

Pinyin tone placement and examples

Tone placement follows the main vowel: a first, then e, then o in ou; otherwise the mark falls on the last vowel. This puts the mark on the second letter in iu and ui. Neutral tone has no mark. Numeric 0 is the standard fallback for neutral tone; this converter also accepts the common 5 alias.

Static examples of Pinyin tone numbers, marks, and ASCII output
Tone numbers Tone marks ASCII-safe
ni3 hao3nǐ hǎoni3 hao3
liu2 shui3liú shuǐliu2 shui3
lü4 cha2lǜ chálv4 cha2

Accent stripping

The strip mode canonically decomposes text, removes characters with the Unicode Diacritic property, and recomposes to NFC. It changes marks in any script, not only Latin accents. Letters such as ø, ł, œ, and ß are letters rather than removable accents and remain in the primary result.

Unicode normalization

NFC and NFD provide composed and decomposed canonical forms. NFKC and NFKD additionally apply compatibility decomposition, which can turn ligatures, width variants, circled numbers, and presentation characters into ordinary equivalents.

ASCII-safe does not mean reversible

ASCII cannot reproduce every Unicode distinction. This tool keeps remaining code points visible as escapes instead of deleting them, but downstream software may not reconstruct the intended typography automatically.

Method, sources, and limitations

Pinyin placement follows GB/T 16159-2012. Unicode forms follow Unicode Standard Annex #15 and the normalization data installed with ICU. Accent stripping and the ASCII representation are transparent local processing profiles, not separate romanization standards.

This independent reference tool does not replace the spelling required by a passport office, immigration office, embassy, library, publisher, school, or national naming authority. Verify important names and official records with the responsible organization.

Frequently asked questions

Why did a number remain unchanged?

The converter changes a tone digit only when it follows a validated Hanyu Pinyin syllable. This protects model numbers, dates, standards, and malformed sequences from accidental conversion.

Does stripping accents transliterate every special letter?

No. It removes Unicode diacritics, while independent letters such as ø or ł remain. The separate ASCII-safe copy can approximate supported Latin letters.

Which normalization form should I use?

NFC is the usual choice for web text. Use NFD when a decomposed representation is required. Use NFKC or NFKD only when intentionally merging compatibility distinctions is acceptable.

Is text stored or added to the page URL?

No. Text is submitted in a short-lived same-origin request, is not saved by this converter, and is not placed in an indexable result URL.