Float vs Double vs Decimal in C#

1. The Float data type in C#
2. The Double data type in C#
3. The Decimal data type in C#
4. Float vs Double vs Decimal in C#

This tutorial will discuss the similarities and differences between Float, Double, and Decimal data types in C#.

The Float data type in C#

The Float data type stores floating-point values in C#. The float keyword is used to declare a float variable. We have to use the f specifier during initialization to tell the compiler that the value is a floating-point value. A float variable is 32bits in size meaning that it can store values from -3.402823e38 to +3.402823e38. A float variable has a precision of 7 digits in C#. The following code example shows us how we can declare a float variable in C#.

using System;

namespace data_types {
  static void Main(string[] args) {
    float fval = 100.0f / 3;
    Console.WriteLine(fval);
  }
}
}

Output:

33.33333

We initialized the float variable fval with the float keyword and the f specifier in C#. The printed output shows that the precision of the fval is only 7 digits.

The Double data type in C#

The Double data type also stores floating-point values in C#. The double keyword is used to declare a double variable. We have to use the d specifier during initialization to tell the compiler that the value is a double value. A double variable is 64bits in size meaning that it can store values from -1.79769313486232e308 to +1.79769313486232e308. A double variable has a precision of 15 digits in C#. The following code example shows us how we can declare a double variable in C#.

using System;

namespace data_types {
  static void Main(string[] args) {
    double dval = 100.0d / 3;
    Console.WriteLine(dval);
  }
}
}

Output:

33.3333333333333

We initialized the double variable dval with the double keyword and the d specifier in C#. The printed output shows that the precision of the dval is 15 digits.

The Decimal data type in C#

The Decimal data type also stores floating-point values in C#. The decimal keyword is used to declare a decimal variable. We have to use the M specifier during initialization to tell the compiler that the value is a decimal value. A decimal variable is 128bits in size meaning that it can store values from -79,228,162,514,264,337,593,543,950,335 to +79,228,162,514,264,337,593,543,950,335. A decimal variable has a precision of 29 digits in C#. The following code example shows us how we can declare a decimal variable in C#.

using System;

namespace data_types {
  static void Main(string[] args) {
    decimal dval = 100.0M / 3;
    Console.WriteLine(dval);
  }
}
}

Output:

33.333333333333333333333333333

We initialized the decimal variable dval with the decimal keyword and the M specifier in C#. The printed output shows that the precision of the dval is 29 digits.

Float vs Double vs Decimal in C#

The float and double data types are lower in precision and size than the decimal data type. So, the decimal data type is recommended for recording sensitive information that requires a large number of significant figures like financial transactions. But, the decimal data type is much slower than the float and double data types. So, whenever we are dealing with some scientific values that are already an approximation and do not require very high precision, we can either use the float or the double data type depending upon our needs.