Text Inspector

Details and how to verify this yourself: Security & privacy.

The tool sits in a window that works like a desktop app: menus on the top row and the full-screen icon at its right (Esc leaves full screen). The set-up options described below are in Settings → Options…, an overlay, and the Settings menu also lists the common choices directly. To keep the options in view instead, choose View → Inline config; the page remembers that choice. Help → Keyboard shortcuts… lists the keys.

1. Paste or type text. It is analysed as-is: nothing is trimmed or normalized.
2. Read the Counts card. Characters are grapheme clusters, what a person would count. The other rows are what programs count:
   • Code points: Python’s len().
   • UTF-16 code units: JavaScript’s .length, Java’s length().
   • UTF-8 bytes: what storage and network limits measure.
3. To count a letter or word, type it in Count occurrences of. Every match is listed with its line, column and index. Tick Ignore case to match R and r alike.
4. The banner turns red if the text contains hidden or deceptive characters, which are listed with their positions:
   • zero-width characters;
   • bidirectional controls;
   • Unicode tag characters;
   • Latin look-alikes from other scripts.
5. Tick Per-character breakdown to see each code point’s U+ number, UTF-8 bytes, Unicode category and script.

Why counts differ. 👍🏽 is one character to a reader, but it is two code points (thumbs up + skin tone), four UTF-16 code units, and eight UTF-8 bytes. é can be one code point (U+00E9) or two (e + U+0301 combining accent), and both look identical. Normalization tells you whether the text is in NFC, the composed form most systems expect.

Hidden characters matter.

• A zero-width space breaks a search, a password or an identifier invisibly.
• Bidirectional overrides can make source code display differently from how it compiles (“Trojan Source”).
• Unicode tag characters can hide instructions that language models read but people cannot see.
• A Cyrillic а in pаypal makes a look-alike domain or username.

Counts.

Line breaks are LF, CRLF (counted once) and CR. lineEndings.style is none, LF, CRLF, CR, or mixed when more than one kind occurs. U+0085, U+2028 and U+2029 are not counted as line breaks; they are reported as line-separator findings.

Character classes count code points by Unicode property: \p{L}, \p{Lu}, \p{Ll}, \p{M}, \p{Nd}, \p{N}, \p{P}, \p{S}, \p{White_Space}, \p{Zs}, \p{Cc} and \p{Cf}. Titlecase letters such as Dž count as letters, but as neither upper nor lower case. emoji counts grapheme clusters containing an \p{Extended_Pictographic} code point.

Occurrences (find).

• Matching: literal (special characters have no meaning) and on code points.
• No normalization: precomposed é does not match e + U+0301.
• Case: case-sensitive by default. With case_sensitive=false, Unicode simple case folding is used: K (Kelvin sign) matches k, but ß does not match ss and İ does not match i.
• count: non-overlapping matches from left to right (aa in aaaa is 2).
• overlappingCount: a match may start at every code point (aa in aaaa is 3).
• Positions: each match has utf16Index, codePointIndex and graphemeIndex (0-based), and line and column (1-based, column in code points). splitsGrapheme is true when a match starts or ends inside a grapheme cluster, such as e inside e + U+0301.
• Limit: at most 1,000 positions are listed; count is always exact.

Hidden and deceptive characters.

Exempted as normal emoji syntax:

• ZWJ inside an emoji grapheme cluster (👨‍👩‍👧);
• tag characters in an emoji tag sequence (U+1F3F4, 1–7 tags, U+E007F, such as the flag of England);
• variation selectors 15 and 16 (U+FE0E, U+FE0F).

Other detection rules.

• Look-alikes: the built-in list covers common look-alikes of ASCII letters. It is a subset of Unicode’s confusables.txt, not the full UTS #39 algorithm.
• Unbalanced bidi controls: bidiUnterminatedLines lists lines where an embedding or override is not closed by U+202C, or an isolate by U+2069, before the line ends. This is the Trojan Source pattern.
• Limit: at most 1,000 findings are listed, in text order; total and byKind are exact.

Per-code-point breakdown (breakdown = N, at most 2,000 through the API, 500 on the page). For each code point:

• its index and U+XXXX;
• UTF-8 and UTF-16 bytes in hex;
• its General_Category, tested against all 30 values;
• its Script, checked against 49 widely used scripts plus Unknown for unassigned code points (null if it is in none of them);
• a name for control, space and invisible characters (null for others: the full Unicode name list is not bundled).

Locale. locale must be a valid BCP 47 tag. It affects word and sentence segmentation; grapheme segmentation is locale-independent in practice.

Versions. Segmentation and properties come from the ICU and Unicode data in the runtime: V8 in Cloudflare Workers for the API, your browser for the page. Counts for newly added emoji can differ between runtimes on different Unicode versions.

API limits. input is at most 20,000 UTF-16 code units (about 6 ms of server CPU, inside the Workers per-request budget); split longer text and add the counts. find is at most 1,000 code units.