Unicode Normalizer

What this tool does

The Unicode Normalizer converts text into one of the four standard Unicode normalization forms: NFC, NFD, NFKC or NFKD. It also shows whether the text changed, how many Unicode code points and UTF-8 bytes were present before and after normalization, and which forms already matched the original or resulting text.

This is useful when two strings look identical but compare as different data. A name copied from one system may contain precomposed letters, while the same-looking name copied from another system may contain a base letter plus combining marks. Normalization gives you a documented way to compare or store text consistently.

Which normalization form should I use?

NFC is the common general-purpose composed form for most text storage and display. It keeps text compact where canonical precomposed characters exist. NFD is the canonical decomposed form and is useful for analysis, accent inspection and some platform-specific workflows. NFKC applies compatibility mappings and can be useful for selected search, matching and identifier workflows. NFKD performs compatibility decomposition and is mainly useful for advanced analysis.

No form is universally safe. Passwords, digital signatures, exact legal records, source data and identifiers with strict external rules need a documented policy before normalization is applied.

NFC vs NFD example

The letter é can be represented as one precomposed code point or as a base letter followed by a combining mark. Under NFD, U+00E9 may normalize to U+0065 U+0301. Under NFC, U+0065 U+0301 may normalize to U+00E9.

NFC: é
Code points: U+00E9

NFD: e + ◌́
Code points: U+0065 U+0301

NFKC and NFKD warning

Compatibility normalization can replace compatibility characters with more ordinary equivalents. Full-width Ａ can become A, the ligature fi can become fi, and circled ① can become 1. This can be useful for search indexes or identifier comparison, but it may lose formatting distinctions and may not be reversible exactly.

Common use cases

• Normalize text before database comparison.
• Diagnose visually identical strings that fail equality checks.
• Prepare search indexes with a documented text policy.
• Compare copied text from macOS, Windows or web pages.
• Inspect combining marks and decomposed accents.
• Normalize selected identifiers under an explicit product or protocol policy.

Privacy

This tool runs in your browser. Entered text is not sent to UnicodeNow servers, stored in PostgreSQL or Redis, logged, added to analytics events, written to URL query strings, or saved in localStorage or sessionStorage by this page.

Technical details

Browser-side processing uses JavaScript String.prototype.normalize() with one of the four valid form names. Code point counts use code point iteration rather than UTF-16 code unit length, and UTF-8 byte counts use TextEncoder. Emoji and supplementary-plane characters remain supported during normalization.

Example

Try this input:

é é Ａ fi ① 😀

With NFD selected, the composed é is decomposed into e plus U+0301 COMBINING ACUTE ACCENT. With NFKC selected, compatibility characters such as Ａ, fi and ① change to standard-width or ordinary equivalents. The emoji remains a supplementary Unicode character.

Frequently asked questions