Count number of characters - Revision history

Planetoid: /* Further reading */

2026-06-10T07:28:14Z

Planetoid: /* Character Count vs. Byte Count Comparison */

2026-06-10T07:27:26Z

Character Count vs. Byte Count Comparison

← Older revision		Revision as of 15:27, 10 June 2026
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	</table>		</table>

	Each Chinese character is approximately 3 bytes in UTF-8		: [[Image:Owl icon.jpg]] Each Chinese character is approximately 3 bytes in UTF-8

			Common Chinese characters (CJK Unified Ideographs, U+4E00 ~ U+9FFF) are all 3 bytes — for example, "你", "好", "狐", and "象". Characters beyond U+FFFF (outside the Basic Multilingual Plane, BMP<ref>[https://en.wikipedia.org/wiki/Plane_(Unicode) Plane (Unicode) - Wikipedia]</ref>) take 4 bytes. These are mostly rare characters from CJK Extension B (U+20000 and up)<ref>[https://en.wikipedia.org/wiki/CJK_Unified_Ideographs_Extension_B CJK Unified Ideographs Extension B - Wikipedia]</ref>, such as "[https://www.cns11643.gov.tw/wordView.jsp?ID=993142 𤆬]" (U+241AC) and "[https://www.cns11643.gov.tw/wordView.jsp?ID=402472 𠮷]" (U+20BB7).

	== How to count characters with PHP ==		== How to count characters with PHP ==

Planetoid at 07:15, 10 June 2026

2026-06-10T07:15:09Z

← Older revision		Revision as of 15:15, 10 June 2026
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	Counting number of characters (or bytes) in different approaches		Counting number of characters (or bytes) in different approaches

			== Character Count vs. Byte Count Comparison ==
	<table border="1" class="wikitable sortable">		<table border="1" class="wikitable sortable">
	<tr>		<tr>
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	<td>敏捷的棕毛狐狸從懶狗身上躍過</td>		<td>敏捷的棕毛狐狸從懶狗身上躍過</td>
	<td>14</td>		<td>14</td>
	<td>28</td>		<td>42</td>
	</tr>		</tr>
	</table>		</table>

			Each Chinese character is approximately 3 bytes in UTF-8

	== How to count characters with PHP ==		== How to count characters with PHP ==

Planetoid: /* How to count characters with BASH */

2024-10-01T10:55:36Z

How to count characters with BASH

← Older revision		Revision as of 18:55, 1 October 2024
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	== How to count characters with BASH ==		== How to count characters with BASH ==
	Step1: Using [https://www.computerhope.com/unix/uwc.htm Linux wc command]		Step1: Using [https://www.computerhope.com/unix/uwc.htm Linux wc command]
			<pre>
			# Count the total number of characters in a file named "input.txt", while ignoring all whitespace characters (including spaces, tabs, newlines, etc.).
			tr -d '\r\n[:space:]' < input.txt \| wc -m
			</pre>


	<pre>		<pre>
	# print the character counts of txt files (contains the count of return symbol)		# print the character counts of txt files (contains the count of return symbol)
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	Number of characters (not contains the [[Return symbol \| return symbol]]) = result of {{kbd \| key=<nowiki>wc -m .txt</nowiki>}} - result of {{kbd \| key=<nowiki>wc -m .txt</nowiki>}} * 2 - 1 (the last blank line costs 1 character) - number of the whitespaces		Number of characters (not contains the [[Return symbol \| return symbol]]) = result of {{kbd \| key=<nowiki>wc -m .txt</nowiki>}} - result of {{kbd \| key=<nowiki>wc -m .txt</nowiki>}} * 2 - 1 (the last blank line costs 1 character) - number of the whitespaces


	== How to count characters with Python ==		== How to count characters with Python ==

Unknown user at 03:35, 30 August 2023

2023-08-30T03:35:56Z

← Older revision		Revision as of 11:35, 30 August 2023
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	</table>		</table>

	== PHP ==		== How to count characters with PHP ==
	* PHP: [https://www.php.net/manual/en/function.strlen.php strlen] & [http://php.net/mb_strlen PHP mb_strlen function]		* PHP: [https://www.php.net/manual/en/function.strlen.php strlen] & [http://php.net/mb_strlen PHP mb_strlen function]

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	</pre>		</pre>

	== MySQL ==		== How to count characters with MySQL ==
	* MySQL: [http://www.w3resource.com/mysql/string-functions/mysql-char_length-function.php MySQL CHAR_LENGTH() function]		* MySQL: [http://www.w3resource.com/mysql/string-functions/mysql-char_length-function.php MySQL CHAR_LENGTH() function]
	<PRE>		<PRE>
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	== SQLite ==		== How to count characters with SQLite ==
	[https://www.sqlitetutorial.net/sqlite-functions/sqlite-length/#targetText=SQLite%20Length,returns%20the%20number%20of%20bytes. Length] function		[https://www.sqlitetutorial.net/sqlite-functions/sqlite-length/#targetText=SQLite%20Length,returns%20the%20number%20of%20bytes. Length] function
	<PRE>		<PRE>
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	</PRE>		</PRE>

	== Excel ==		== How to count characters with Excel ==
	* Excel: [https://support.office.com/en-us/article/len-lenb-functions-29236f94-cedc-429d-affd-b5e33d2c67cb LEN, LENB functions] / [https://support.office.com/zh-tw/article/LEN%E3%80%81LENB-%E5%87%BD%E6%95%B8-29236f94-cedc-429d-affd-b5e33d2c67cb LEN、LENB 函數] {{exclaim}} Result of the function {{kbd \| key=LENB}} is not the same with the result in other programming language.		* Excel: [https://support.office.com/en-us/article/len-lenb-functions-29236f94-cedc-429d-affd-b5e33d2c67cb LEN, LENB functions] / [https://support.office.com/zh-tw/article/LEN%E3%80%81LENB-%E5%87%BD%E6%95%B8-29236f94-cedc-429d-affd-b5e33d2c67cb LEN、LENB 函數] {{exclaim}} Result of the function {{kbd \| key=LENB}} is not the same with the result in other programming language.
	<pre>		<pre>
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	* [https://stackoverflow.com/questions/5290182/how-many-bytes-does-one-unicode-character-take string - How many bytes does one Unicode character take? - Stack Overflow]		* [https://stackoverflow.com/questions/5290182/how-many-bytes-does-one-unicode-character-take string - How many bytes does one Unicode character take? - Stack Overflow]

	== BASH ==		== How to count characters with BASH ==
	Step1: Using [https://www.computerhope.com/unix/uwc.htm Linux wc command]		Step1: Using [https://www.computerhope.com/unix/uwc.htm Linux wc command]
	<pre>		<pre>
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	== Python ==		== How to count characters with Python ==
	Using the [https://docs.python.org/3/library/functions.html#len len()] function<ref>[https://stackoverflow.com/questions/30686701/python-get-size-of-string-in-bytes Python : Get size of string in bytes - Stack Overflow]</ref>. Try it on [https://replit.com/@planetoid/lenth-of-string#main.py replit].		Using the [https://docs.python.org/3/library/functions.html#len len()] function<ref>[https://stackoverflow.com/questions/30686701/python-get-size-of-string-in-bytes Python : Get size of string in bytes - Stack Overflow]</ref>. Try it on [https://replit.com/@planetoid/lenth-of-string#main.py replit].

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	== JavaScript ==		== How to count characters with JavaScript ==
	Using the [https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/length length()] function and [https://developer.mozilla.org/en-US/docs/Web/API/Blob Blob] object <ref> [https://stackoverflow.com/questions/2219526/how-many-bytes-in-a-javascript-string How many bytes in a JavaScript string? - Stack Overflow]</ref>.		Using the [https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/length length()] function and [https://developer.mozilla.org/en-US/docs/Web/API/Blob Blob] object <ref> [https://stackoverflow.com/questions/2219526/how-many-bytes-in-a-javascript-string How many bytes in a JavaScript string? - Stack Overflow]</ref>.

Unknown user: /* PHP */

2023-03-08T03:29:03Z

PHP

← Older revision		Revision as of 11:29, 8 March 2023
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	== PHP ==		== PHP ==
	* PHP: [https://www.php.net/manual/en/function.strlen.php strlen] & [http://php.net/mb_strlen PHP mb_strlen function]		* PHP: [https://www.php.net/manual/en/function.strlen.php strlen] & [http://php.net/mb_strlen PHP mb_strlen function]

			Number of characters
	<pre>		<pre>
	~~// number of characters~~
	echo mb_strlen("狐", 'UTF-8') . PHP_EOL; // return 1		echo mb_strlen("狐", 'UTF-8') . PHP_EOL; // return 1
	echo mb_strlen("《王大文 Dawen》", 'UTF-8') . PHP_EOL; // return 11		echo mb_strlen("《王大文 Dawen》", 'UTF-8') . PHP_EOL; // return 11
			</pre>

	~~// string~~ length (number of bytes)		String length (number of bytes)
			<pre>
	echo strlen("狐") . PHP_EOL; // return 3		echo strlen("狐") . PHP_EOL; // return 3
	echo strlen("《王大文 Dawen》") . PHP_EOL; // return 21		echo strlen("《王大文 Dawen》") . PHP_EOL; // return 21
			</pre>

			Number of words {{exclaim}} [https://www.php.net/manual/en/function.str-word-count.php str_word_count] function not support Chinese characters
			<pre>
			echo str_word_count("The quick brown fox jumps over the lazy dog"); // return 9
			echo str_word_count("敏捷的棕毛狐狸從懶狗身上躍過"); // return 0
	</pre>		</pre>

Unknown user: /* References */

2022-05-02T14:29:26Z

References

← Older revision		Revision as of 22:29, 2 May 2022
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	== References ==		== References ==
	<references />		<references />

			== Further reading ==

			* [https://www.ithome.com.tw/voice/131688 Unicode與JavaScript字串 \| iThome]

	[[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation]] [[Category:PHP]] [[Category:MySQL]]		[[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation]] [[Category:PHP]] [[Category:MySQL]]

Unknown user at 01:51, 2 May 2022

2022-05-02T01:51:07Z

← Older revision		Revision as of 09:51, 2 May 2022
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	<references />		<references />

	[[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation~~]] [[Category:Data transformation]]~~		[[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation]] [[Category:PHP]] [[Category:MySQL]]
	~~[[Category:Regular expression~~]] [[Category:PHP]] [[Category:MySQL]]

Unknown user: /* Python */

2022-05-02T01:47:36Z

Python

← Older revision		Revision as of 09:47, 2 May 2022
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	</pre>		</pre>


			== JavaScript ==
			Using the [https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/length length()] function and [https://developer.mozilla.org/en-US/docs/Web/API/Blob Blob] object <ref> [https://stackoverflow.com/questions/2219526/how-many-bytes-in-a-javascript-string How many bytes in a JavaScript string? - Stack Overflow]</ref>.

			=== Get the number of characters in a string in JavaScript ===

			<pre>
			var string = "狐"
			console.log(string.length);
			</pre>

			=== Get the number of bytes in a string in JavaScript ===

			<pre>
			var string = "狐"
			console.log(new Blob([string]).size);
			// returns 3
			</pre>

	== References ==		== References ==

Unknown user: python

2022-05-02T01:25:43Z

python

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 Number of characters (not contains the [[Return symbol | return symbol]]) = result of {{kbd | key=<nowiki>wc -m *.txt</nowiki>}} - result of {{kbd | key=<nowiki>wc -m *.txt</nowiki>}} * 2 - 1 (the last blank line costs 1 character) - number of the whitespaces
 [[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation]] [[Category:Data transformation]]
 [[Category:Regular expression]] [[Category:PHP]] [[Category:MySQL]]

← Older revision		Revision as of 15:28, 10 June 2026
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	* [https://www.ithome.com.tw/voice/131688 Unicode與JavaScript字串 \| iThome]		* [https://www.ithome.com.tw/voice/131688 Unicode與JavaScript字串 \| iThome]

	[[Category:Software]] [[Category:Programming]] [[Category:Data Science]] [[Category:String manipulation]] [[Category:PHP]] [[Category:MySQL]]		[[Category: Software]]
			[[Category: Programming]]
			[[Category: Data Science]]
			[[Category: String manipulation]]
			[[Category: PHP]]
			[[Category: MySQL]]
			[[Category: Revised with LLMs]]