Count number of characters

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Counting number of characters (or bytes) in different approaches

String example Number of characters Number of bytes
fox 3 3
The quick brown fox jumps over the lazy dog 43 43
1 3
1 3
🐘 1 4
敏捷的棕毛狐狸從懶狗身上躍過 14 28

PHP[edit]

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

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

MySQL[edit]

// number of characters
SELECT CHAR_LENGTH("狐"); /* return 1 */
SELECT CHAR_LENGTH("《王大文 Dawen》"); /* return 11 */

// number of bytes
SELECT LENGTH("狐"); /* return 3 */
SELECT LENGTH("《王大文 Dawen》"); /* return 21 */


SQLite[edit]

Length function

SELECT LENGTH("狐"); /* return 1 */
SELECT LENGTH("《王大文 Dawen》"); /* return 11 */

Excel[edit]

// number of characters
=LEN("狐") // return 1
=LEN("《王大文 Dawen》") // return 11

// number of bytes
=LENB("狐") // return 2
=LENB("《王大文 Dawen》") // return 16

BASH[edit]

Step1: Using Linux wc command

# print the character counts of txt files (contains the count of return symbol)
wc -m *.txt

# print the newline counts of txt files
wc -l *.txt

# print the whitespaces counts of txt files
grep -c ' ' *.txt

Step2: Check the Return symbol

  • e.g. \r\n costs 2 characters

Step3: final formula

Number of characters (not contains the return symbol) = result of wc -m *.txt - result of wc -m *.txt * 2 - 1 (the last blank line costs 1 character) - number of the whitespaces


Python[edit]

Using the len() function[1]. Try it on replit.

Get the number of characters in a string in Python[edit]

string = "狐"
print(len(string))
// returns 1

Get the number of bytes in a string in Python[edit]

string = "狐"
print(len(string.encode('utf-8')))
// returns 3

print(len(string.encode('utf-16-le')))
// returns 2


JavaScript[edit]

Using the length() function and Blob object [2].

Get the number of characters in a string in JavaScript[edit]

var string = "狐"
console.log(string.length);

Get the number of bytes in a string in JavaScript[edit]

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

References[edit]

Further reading[edit]