#import <CommonCrypto/CommonDigest.h>


+ (NSString *) md5:(NSString *)str {
 const char *cStr = [str UTF8String];
 unsigned char result[16];
 CC_MD5( cStr, strlen(cStr), result );
 return [NSString stringWithFormat:
  @"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
  result[0], result[1], result[2], result[3], 
  result[4], result[5], result[6], result[7],
  result[8], result[9], result[10], result[11],
  result[12], result[13], result[14], result[15]
  ]; 
}

Compute an MD5 hash on iphone

Objective C