Most developers when requiring a integer type use the int type and go about their business.

The largest int you can use is 2,147,483,647, and the smallest is -2,147,483,647. int is a 32 bit type

This is a very big range - 4,294,967,295

Int is a signed type - has provisions for - and + numbers.

There is an unsigned version - uint

This one has a minimum of 0 and a maximum of 4,294,967,295

You can establish the minimum of the int (or any numeric type for that matter) as follows:

Console.WriteLine(int.MinValue);

Similarly, for the maximum value

Console.WriteLine(int.MaxValue);

In the context of storage - for instance if using Entity Framework - the size of the type can start to matter when you are storing very large numbers of values.

For more efficient storage (depending on your use case) you might find it more prudent to default to alternative types.

Name Minimum Maximum Signed? Size (bits)
sbyte -128 127 Yes 8
byte 0 255 No 8
short -32,767 32,767 Yes 16
ushort 0 65,535 No 16

There are also types bigger than the 32 bit integer (a consideration, for example, when specifying integral primary keys in Entity Framework)

Name Minimum Maximum Signed? Size (bits)
long -9,223,372,036,854,775,808 9,223,372,036,854,775,808 Yes 64
ulong 0 18,446,744,073,709,551,615 Yes 64

There are some integral types whose size depends on the underlying platform - native integer (nint), and native unsigned integer (nuint).

The minimum, maximum and size depends on the underlying platform - so either 32 or 64 bits. You should only use these if you know what you are doing.

Finally, for very big numbers of arbitrary size, there is a specialized type for these - System.Numerics.BigInteger

Happy hacking!