Date.today()<\/code>, while others run on a value, such as name.toUpperCase()<\/code>.<\/p>\n\n\n\nWhat Are Apex Built-in Methods?<\/h2>\n\n\n\n
Built-in methods come with the Apex language. They belong to system classes like String<\/code>, Date<\/code>, Datetime<\/code>, Decimal<\/code> and Math<\/code>. You can call them anywhere in your code without creating or deploying anything.<\/p>\n\n\n\nThink of a kitchen that already has a peeler, a grater and a measuring cup. You could cut and measure everything with one knife, but the right tool is faster and gives a cleaner result. Apex Built-in Methods are those ready tools.<\/p>\n\n\n\n
Why Apex Built-in Methods Matter<\/h2>\n\n\n\n
Hand-written code for common tasks is slow to write and easy to get wrong. However, Salesforce tests every built-in method, and each one works the same way in every org.<\/p>\n\n\n\n
\n- Less code.<\/strong> One call like
name.split(' ')<\/code> replaces a whole loop.<\/li>\n\n- Fewer bugs.<\/strong> Date maths handles leap years and month lengths for you.<\/li>\n\n
- Clearer code.<\/strong>
startDate.addDays(30)<\/code> reads like plain English.<\/li>\n\n- Correct money maths.<\/strong>
setScale<\/code> rounds fees in a predictable way.<\/li>\n\n- Interview ready.<\/strong> Many coding questions test String and Date methods.<\/li>\n<\/ul>\n\n\n\n
How Apex Built-in Methods Work<\/h2>\n\n\n\n
There are two ways to call them. You call static methods on the class name, such as String.isBlank(name)<\/code> or Date.today()<\/code>. In contrast, you call instance methods on a value, such as name.length()<\/code> or startDate.addDays(7)<\/code>.<\/p>\n\n\n\n![\"Apex](\"https:\/\/swapnilzambare.com\/blog\/wp-content\/uploads\/2026\/10\/apex-built-in-methods-string-date-math-diagram-1-1024x640.png\")
<\/a>Common built-in methods grouped by class.<\/figcaption><\/figure>\n\n\n\nMost methods return a new value instead of changing the original. For example, name.toUpperCase()<\/code> gives you an uppercase copy, but name<\/code> itself stays the same. So you must store the result in a variable if you want to keep it.<\/p>\n\n\n\nString Methods<\/h2>\n\n\n\n
Strings hold text, and you will work with text in almost every class. The table below lists the String methods you will reach for most often.<\/p>\n\n\n\nMethod<\/th> Example<\/th> Result<\/th><\/tr><\/thead> length()<\/td> ‘Apex Basics’.length()<\/td> 11<\/td><\/tr> toUpperCase()<\/td> ‘apex’.toUpperCase()<\/td> APEX<\/td><\/tr> contains(text)<\/td> ‘Apex Basics’.contains(‘Basics’)<\/td> true<\/td><\/tr> startsWith(text)<\/td> ‘APX-101’.startsWith(‘APX’)<\/td> true<\/td><\/tr> substring(start, end)<\/td> ‘Apex Basics’.substring(0, 4)<\/td> Apex<\/td><\/tr> split(separator)<\/td> ‘a,b,c’.split(‘,’)<\/td> (a, b, c)<\/td><\/tr> trim()<\/td> ‘ Apex ‘.trim()<\/td> Apex<\/td><\/tr> replace(old, new)<\/td> ‘Apex 101’.replace(‘101’, ‘201’)<\/td> Apex 201<\/td><\/tr> String.isBlank(text)<\/td> String.isBlank(‘ ‘)<\/td> true<\/td><\/tr> String.join(list, sep)<\/td> String.join(names, ‘, ‘)<\/td> Asha, Ravi<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nImportant String Details<\/h3>\n\n\n\n
String positions start at 0, just like List indexes. So substring(0, 4)<\/code> takes the characters at positions 0, 1, 2 and 3. The end position itself is not included.<\/p>\n\n\n\nString.isBlank<\/code> is safer than checking name == ''<\/code>. It returns true for null, empty text and text that holds only spaces. So it covers all three “nothing here” cases at once.<\/p>\n\n\n\nFor messages with many values, String.format<\/code> is cleaner than many plus signs. You write placeholders like {0}<\/code> and {1}<\/code>, then pass the values in a list.<\/p>\n\n\n\nDate and Datetime Methods<\/h2>\n\n\n\n
Dates appear in every business process, from course start dates to payment due dates. The table below shows the Date methods you will use most.<\/p>\n\n\n\nMethod<\/th> Example<\/th> Result<\/th><\/tr><\/thead> Date.today()<\/td> Date.today()<\/td> Today’s date<\/td><\/tr> Date.newInstance(y, m, d)<\/td> Date.newInstance(2026, 9, 15)<\/td> 15 September 2026<\/td><\/tr> addDays(n)<\/td> d.addDays(30)<\/td> 30 days later<\/td><\/tr> addMonths(n)<\/td> d.addMonths(2)<\/td> 2 months later<\/td><\/tr> daysBetween(other)<\/td> start.daysBetween(endDate)<\/td> Number of days<\/td><\/tr> toStartOfMonth()<\/td> d.toStartOfMonth()<\/td> First day of that month<\/td><\/tr> year(), month(), day()<\/td> d.month()<\/td> 9<\/td><\/tr> Datetime.now()<\/td> Datetime.now()<\/td> Current date and time<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nPass a negative number to go back in time. For example, Date.today().addDays(-7)<\/code> gives the date one week ago. The addMonths<\/code> method also handles short months correctly, so 31 January plus one month gives 28 or 29 February.<\/p>\n\n\n\nDatetime<\/code> values include a time and a time zone. The format<\/code> method shows them in the running user’s time zone. For example, Datetime.now().format('dd-MM-yyyy HH:mm')<\/code> gives something like 15-09-2026 14:30<\/code>.<\/p>\n\n\n\nMath and Decimal Methods<\/h2>\n\n\n\n
The Math<\/code> class covers common number tasks, while Decimal<\/code> has its own methods for rounding money. The table below shows the most useful ones.<\/p>\n\n\n\nMethod<\/th> Example<\/th> Result<\/th><\/tr><\/thead> Math.abs(n)<\/td> Math.abs(-250)<\/td> 250<\/td><\/tr> Math.max(a, b)<\/td> Math.max(4500, 6000)<\/td> 6000<\/td><\/tr> Math.min(a, b)<\/td> Math.min(4500, 6000)<\/td> 4500<\/td><\/tr> Math.mod(a, b)<\/td> Math.mod(47, 10)<\/td> 7<\/td><\/tr> Math.ceil(n)<\/td> Math.ceil(4.2)<\/td> 5<\/td><\/tr> Math.floor(n)<\/td> Math.floor(4.8)<\/td> 4<\/td><\/tr> setScale(2, mode)<\/td> fee.setScale(2, RoundingMode.HALF_UP)<\/td> 1234.57 when fee is 1234.565<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nRemember from the operators post that Apex has no %<\/code> operator. So Math.mod<\/code> is the only way to get a remainder. For money, always use setScale<\/code> with a clear rounding mode, so every invoice rounds the same way.<\/p>\n\n\n\nA Real Apex Built-in Methods Example<\/h2>\n\n\n\n
Let’s build a small helper for Bright Path Tutors. It takes a course name, a fee and a start date. Then it creates a course code, an end date six weeks later and a monthly instalment.<\/p>\n\n\n\n
public with sharing class CourseInfoHelper {\n\n public static String courseCode(String name) {\n if (String.isBlank(name)) {\n return 'NA';\n }\n List<String> words = name.trim().split('\\\\s+');\n String code = '';\n for (String w : words) {\n code += w.substring(0, 1).toUpperCase();\n }\n return code + '-' + Date.today().year();\n }\n\n public static Date endDate(Date startDate, Integer weeks) {\n return startDate.addDays(weeks * 7);\n }\n\n public static Decimal monthlyInstalment(Decimal fee, Integer months) {\n return (fee \/ months).setScale(2, RoundingMode.HALF_UP);\n }\n}<\/code><\/pre>\n\n\n\nThe courseCode<\/code> method first guards against empty names with String.isBlank<\/code>. Then trim<\/code> removes outer spaces, and split('\\\\s+')<\/code> breaks the name into words, even when there are double spaces between them. The loop takes the first letter of each word with substring(0, 1)<\/code> and makes it uppercase. Finally, it adds the current year.<\/p>\n\n\n\nNext, endDate<\/code> uses addDays<\/code> to move the date forward by the number of weeks. Then monthlyInstalment<\/code> divides the fee and rounds it to two decimals with setScale<\/code>.<\/p>\n\n\n\nHere is how to call it from anonymous Apex.<\/p>\n\n\n\n
Date start = Date.newInstance(2026, 9, 15);\n\nSystem.debug(CourseInfoHelper.courseCode('salesforce apex basics'));\nSystem.debug(CourseInfoHelper.endDate(start, 6).format());\nSystem.debug(CourseInfoHelper.monthlyInstalment(10000, 3));\nSystem.debug(start.daysBetween(CourseInfoHelper.endDate(start, 6)) + ' days');<\/code><\/pre>\n\n\n\nThe log shows the code, the end date in your locale format, the instalment and the length in days.<\/p>\n\n\n\n
USER_DEBUG [3]|DEBUG|SAB-2026\nUSER_DEBUG [4]|DEBUG|27\/10\/2026\nUSER_DEBUG [5]|DEBUG|3333.33\nUSER_DEBUG [6]|DEBUG|42 days<\/code><\/pre>\n\n\n\nYour date format may differ, because format()<\/code> follows the user’s locale setting. An Indian English locale shows 27\/10\/2026, while a US locale shows 10\/27\/2026.<\/p>\n\n\n\nApex Built-in Methods vs Writing Your Own<\/h2>\n\n\n\n
Should you ever write your own version of a built-in method? The table below compares the two approaches.<\/p>\n\n\n\nFeature<\/th> Built-in method<\/th> Your own code<\/th><\/tr><\/thead> Time to write<\/td> None<\/td> Minutes to hours<\/td><\/tr> Tested by<\/td> Salesforce<\/td> You<\/td><\/tr> Handles edge cases<\/td> Yes, such as leap years<\/td> Only if you remember them<\/td><\/tr> Readability<\/td> High, well-known names<\/td> Depends on your naming<\/td><\/tr> When it fits<\/td> Common tasks<\/td> Rules unique to your business<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
![\"Apex](\"https:\/\/swapnilzambare.com\/blog\/wp-content\/uploads\/2026\/10\/apex-built-in-methods-string-date-math-diagram-2-1024x640.png\")
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