Menu
×
NEW W3Schools app iOS & Android Start the adventure Spaces Upgrade Paid Courses Spaces Upgrade Paid Courses
   ❮     
HTML CSS JAVASCRIPT SQL PYTHON JAVA PHP C C++ C# AWS W3.CSS HOW TO BOOTSTRAP REACT MYSQL JQUERY EXCEL XML DJANGO NUMPY PANDAS NODEJS DSA TYPESCRIPT ANGULAR ANGULARJS GIT POSTGRESQL MONGODB ASP AI R GO KOTLIN SWIFT SASS VUE GEN AI SCIPY CYBERSECURITY DATA SCIENCE INTRO TO PROGRAMMING INTRO TO HTML & CSS BASH RUST TOOLS

Java Tutorial

Java HOME Java Intro Java Get Started Java Syntax
Syntax Statements Code Challenge
Java Output
Print Text Print Numbers Code Challenge
Java Comments Java Variables
Variables Print Variables Multiple Variables Identifiers Constants (Final) Real-Life Examples Code Challenge
Java Data Types
Data Types Numbers Booleans Characters Real-Life Example Non-primitive Types The var Keyword Code Challenge
Java Type Casting Java Operators
Operators Arithmetic Assignment Comparison Logical Precedence Code Challenge
Java Strings
Strings Concatenation Numbers and Strings Special Characters StringBuilder Code Challenge
Java Math Java Booleans
Booleans Real-Life Example Code Challenge
Java If...Else
if else else if Short Hand If...Else Nested If Logical Operators Real-Life Examples Code Challenge
Java Switch
Switch Code Challenge
Java While Loop
While Loop Do/While Loop Real-Life Examples Code Challenge
Java For Loop
For Loop Nested Loops For-Each Loop Real-Life Examples Code Challenge
Java Break/Continue Java Arrays
Arrays Loop Through an Array Real-Life Examples Multidimensional Arrays Code Challenge

Java Methods

Java Methods Java Method Challenge Java Method Parameters
Parameters Return Values Code Challenge
Java Method Overloading Java Scope Java Recursion

Java Classes

Java OOP Java Classes/Objects Java Class Attributes Java Class Methods Java Class Challenge Java Constructors Java this Keyword Java Modifiers
Access Modifiers Non-Access Modifiers
Java Encapsulation Java Packages / API Java Inheritance Java Polymorphism Java super Keyword Java Inner Classes Java Abstraction Java Interface Java Anonymous Java Enum
Enums Enum Constructor
Java User Input Java Date

Java Errors

Java Errors Java Debugging Java Exceptions Java Multiple Exceptions Java try-with-resources

Java File Handling

Java Files Java Create Files Java Write Files Java Read Files Java Delete Files

Java I/O Streams

Java I/O Streams Java FileInputStream Java FileOutputStream Java BufferedReader Java BufferedWriter

Java Data Structures

Java Data Structures Java Collections Java List Java ArrayList Java LinkedList Java List Sorting Java Set Java HashSet Java TreeSet Java LinkedHashSet Java Map Java HashMap Java TreeMap Java LinkedHashMap Java Iterator Java Algorithms

Java Advanced

Java Wrapper Classes Java Generics Java Annotations Java RegEx Java Threads Java Lambda Java Optional Java Advanced Sorting

Java Projects

Java Projects

Java Cert

Java Certificate

Java How To's

Java How Tos
How Tos Add Two Numbers Swap Two Variables Even or Odd Number Reverse a Number Positive or Negative Square Root Area of Rectangle Celsius to Fahrenheit Sum of Digits Check Armstrong Num Random Number Count Words Count Vowels in a String Remove Vowels Count Digits in a String Reverse a String Palindrome Check Check Anagram Convert String to Array Remove Whitespace Count Character Frequency Sum of Array Elements Find Array Average Sort an Array Find Smallest Element Find Largest Element Second Largest Array Min and Max Array Merge Two Arrays Remove Duplicates Find Duplicates Shuffle an Array Factorial of a Number Fibonacci Sequence Find GCD Check Prime Number ArrayList Loop HashMap Loop Loop Through an Enum

Java Reference

Java Reference Java Keywords
assert abstract boolean break byte case catch char class continue default do double else enum exports extends final finally float for if implements import instanceof int interface long module native new package private protected public return requires short static super switch synchronized this throw throws transient try var void volatile while
Java String Methods
charAt() codePointAt() codePointBefore() codePointCount() compareTo() compareToIgnoreCase() concat() contains() contentEquals() copyValueOf() endsWith() equals() equalsIgnoreCase() format() getBytes() getChars() hashCode() indexOf() isEmpty() join() lastIndexOf() length() matches() offsetByCodePoints() regionMatches() replace() replaceAll() replaceFirst() split() startsWith() subSequence() substring() toCharArray() toLowerCase() toString() toUpperCase() trim() valueOf()
Java StringBuilder Methods
append() appendCodePoint() capacity() charAt() codePointAt() codePointBefore() codePointCount() delete() deleteCharAt() ensureCapacity() getChars() indexOf() insert() lastIndexOf() length() offsetByCodePoints() replace() reverse() setCharAt() setLength() subSequence() substring() toString() trimToSize()
Java Math Methods
abs() acos() addExact() asin() atan() atan2() cbrt() ceil() copySign() cos() cosh() decrementExact() exp() expm1() floor() floorDiv() floorMod() getExponent() hypot() IEEEremainder() incrementExact() log() log10() log1p() max() min() multiplyExact() negateExact() nextAfter() nextDown() nextUp() pow() random() rint() round() scalb() signum() sin() sinh() sqrt() subtractExact() tan() tanh() toDegrees() toIntExact() toRadians() ulp()
Java Output Methods
print() printf() println()
Java Arrays Methods
compare() equals() sort() fill() length
Java ArrayList Methods
add() addAll() clear() clone() contains ensureCapacity() forEach() get() indexOf() isEmpty() iterator() lastIndexOf() listIterator() remove() removeAll() removeIf() replaceAll() retainAll() set() size() sort() spliterator() subList() toArray() trimToSize()
Java LinkedList Methods
add() addAll() clear() clone() contains forEach() get() getFirst() getLast() indexOf() isEmpty() iterator() lastIndexOf() listIterator() remove() removeAll() removeFirst() removeIf() removeLast() replaceAll() retainAll() set() size() sort() spliterator() subList() toArray()
Java HashMap Methods
clear() clone() compute() computeIfAbsent() computeIfPresent() containsKey() containsValue() entrySet() forEach() get() getOrDefault() isEmpty() keySet() merge() put() putAll() putIfAbsent() remove() replace() replaceAll() size() values()
Java Scanner Methods
close() delimiter() findInLine() findWithinHorizon() hasNext() hasNextBoolean() hasNextByte() hasNextDouble() hasNextFloat() hasNextInt() hasNextLine() hasNextLong() hasNextShort() locale() next() nextBoolean() nextByte() nextDouble() nextFloat() nextInt() nextLine() nextLong() nextShort() radix() reset() useDelimiter() useLocale() useRadix()
Java File Methods Java FileInputStream Java FileOutputStream Java BufferedReader Java BufferedWriter Java Iterator Methods Java Collections Methods Java System Methods Java Errors & Exceptions

Java Examples

Java Examples Java Videos Java Compiler Java Exercises Java Quiz Java Code Challenges Java Practice Problems Java Server Java Syllabus Java Study Plan Java Interview Q&A


Java StringBuilder length() Method

❮ StringBuilder Methods

Example

Return the number of characters in a StringBuilder:

StringBuilder sb = new StringBuilder("Hello");
System.out.println(sb.length());

Try it Yourself »

Share

Definition and Usage

The length() method returns the number of characters in a StringBuilder.

Tip: The length is not the same as the capacity.

Syntax

public int length()

Parameter Values

None.

Technical Details

Returns: An int value, representing the number of characters.

Related Pages

Java StringBuilder Tutorial

Java String length() Method

❮ StringBuilder Methods
This way to the W3Schools Adventure app
Learn more about Adventure Mode›

Free account

Track your progress

XP earned 0 Day streak 0 Spaces 0 League —

New

Learn in Adventure Mode W3Schools Adventure App

Coding fundamentals as bite-sized lessons and challenges.

Download on the App Store GET IT ON Google Play TRY NOW IN Browser
PLUS
SPACES
GET CERTIFIED
FOR TEACHERS
PRACTICE
CONTACT US
×

Contact Sales

If you want to use W3Schools services as an educational institution, team or enterprise, send us an e-mail:
sales@w3schools.com

Report Error

If you want to report an error, or if you want to make a suggestion, send us an e-mail:
help@w3schools.com

Top Tutorials
HTML Tutorial
CSS Tutorial
JavaScript Tutorial
How To Tutorial
SQL Tutorial
Python Tutorial
W3.CSS Tutorial
Bootstrap Tutorial
PHP Tutorial
Java Tutorial
C++ Tutorial
jQuery Tutorial
Top References
HTML Reference
CSS Reference
JavaScript Reference
SQL Reference
Python Reference
W3.CSS Reference
Bootstrap Reference
PHP Reference
HTML Colors
Java Reference
AngularJS Reference
jQuery Reference
Top Examples
HTML Examples
CSS Examples
JavaScript Examples
How To Examples
SQL Examples
Python Examples
W3.CSS Examples
Bootstrap Examples
PHP Examples
Java Examples
XML Examples
jQuery Examples
Get Certified
 HTML Certificate
CSS Certificate
JavaScript Certificate
Front End Certificate
SQL Certificate
Python Certificate
PHP Certificate
jQuery Certificate
Java Certificate
C++ Certificate
C# Certificate
XML Certificate
FORUM ABOUT CAMPUS
W3Schools is optimized for learning and training. Examples might be simplified to improve reading and learning.
Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness
of all content. While using W3Schools, you agree to have read and accepted our terms of use, cookies and privacy policy.

Copyright 1999-2026 by Refsnes Data. All Rights Reserved. W3Schools is Powered by W3.CSS.