This is a good overview:
http://reference.jumpingmonkey.org/programming_languages/objective-c/types.html
or run this code
NSLog(@"Primitive sizes:"); NSLog(@"The size of a char is: %d.", sizeof(char)); NSLog(@"The size of short is: %d.", sizeof(short)); NSLog(@"The size of int is: %d.", sizeof(int)); NSLog(@"The size of long is: %d.", sizeof(long)); NSLog(@"The size of long long is: %d.", sizeof(long long)); NSLog(@"The size of a unsigned char is: %d.", sizeof(unsigned char)); NSLog(@"The size of unsigned short is: %d.", sizeof(unsigned short)); NSLog(@"The size of unsigned int is: %d.", sizeof(unsigned int)); NSLog(@"The size of unsigned long is: %d.", sizeof(unsigned long)); NSLog(@"The size of unsigned long long is: %d.", sizeof(unsigned long long)); NSLog(@"The size of a float is: %d.", sizeof(float)); NSLog(@"The size of a double is %d.", sizeof(double)); NSLog(@"Ranges:"); NSLog(@"CHAR_MIN: %c", CHAR_MIN); NSLog(@"CHAR_MAX: %c", CHAR_MAX); NSLog(@"SHRT_MIN: %hi", SHRT_MIN); // signed short int NSLog(@"SHRT_MAX: %hi", SHRT_MAX); NSLog(@"INT_MIN: %i", INT_MIN); NSLog(@"INT_MAX: %i", INT_MAX); NSLog(@"LONG_MIN: %li", LONG_MIN); // signed long int NSLog(@"LONG_MAX: %li", LONG_MAX); NSLog(@"ULONG_MAX: %lu", ULONG_MAX); // unsigned long int NSLog(@"LLONG_MIN: %lli", LLONG_MIN); // signed long long int NSLog(@"LLONG_MAX: %lli", LLONG_MAX); NSLog(@"ULLONG_MAX: %llu", ULLONG_MAX); // unsigned long long int
When run on an iPhone 3GS (iPod Touch and older iPhones should yield the same result) you get:
Primitive sizes:
The size of a char is: 1. The size of short is: 2. The size of int is: 4. The size of long is: 4. The size of long long is: 8. The size of a unsigned char is: 1. The size of unsigned short is: 2. The size of unsigned int is: 4. The size of unsigned long is: 4. The size of unsigned long long is: 8. The size of a float is: 4. The size of a double is 8. Ranges: CHAR_MIN: -128 CHAR_MAX: 127 SHRT_MIN: -32768 SHRT_MAX: 32767 INT_MIN: -2147483648 INT_MAX: 2147483647 LONG_MIN: -2147483648 LONG_MAX: 2147483647 ULONG_MAX: 4294967295 LLONG_MIN: -9223372036854775808 LLONG_MAX: 9223372036854775807 ULLONG_MAX: 18446744073709551615