C++ floor()

C++ floor() returns floor value of given decimal number.

Floor value is the largest integer value less than the given number.


The syntax of C++ floor() is



xA double, float, long double, or any integral type value.


The return value depends on the type of value passed for parameter x.

The return value of floor(x) is

  • double if x is double.
  • float if x is float.
  • long double if x is long double.

The synopsis of floor() function is

double floor(double x);
float floor(float x);
long double floor(long double x);
double floor(T x); // For integral type

floor() is a function of cmath library. Include cmath library in the program, if using floor() function.


In this example, we read a double value from user into x, and find its floor value using floor() function.

C++ Program

#include <iostream>
using namespace std;

int main() {
    double x;
    cout << "Enter a number : ";
    cin >> x;
    double result = floor(x);
    cout << "floor(" << x << ") : " << result << endl;


Enter a number : 3.14
floor(3.14) : 3
Program ended with exit code: 0
Enter a number : 3.89
floor(3.89) : 3
Program ended with exit code: 0
Enter a number : 3
floor(3) : 3
Program ended with exit code: 0


In this C++ Tutorial, we learned the syntax of C++ floor(), and how to use this function to find the floor value of given number, with the help of examples.