How to Reverse a Number in JavaScript with Examples

2026 - April - 05

why used reverse ?

A reverse loop is used process data end to the start, useful for like reversing number .

I will give flowchat

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Coding

1. create 3 veriable
   i.num -> store the give value
   ii.rev -> store the reverse value
   iii.digit-> store the last digit value

2. next while loop condition num greater than 0 (0 > 0 ) condition fail loop stop

3. digit num % 10 gets the last digit ,
   why 10 ?
   We use 10 because numbers are in the decimal
   used in divides,multiple..

4. rev*10 + digit value store in rev

5. Same time give decimal number can't run
   Modify in without decimal used Math.floor
   num/10 removes last digit

6. Run repeat in loop fail

7. Print in Output 3210987

8. stop entire program
   

% 10 → last digit
reverse * 10 + digit → build reverse
/ 10 → remove last digit

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