The modified SHA1 algorithm has been developed by expanding its hash value up to 1280 bits from the original size of 160 bit. This was done by allocating 32 buffer registers for variables A, B, C and D at 5 bytes each. The expansion was done by generating 4 buffer registers in every round inside the compression function for 8 times. Findings revealed that the hash value of the modified algorithm was not cracked or hacked during the experiment and testing using powerful online cracking tool, brute force and rainbow table such as Cracking Station and Rainbow Crack and bruteforcer which are available online thus improved its security level compared to the original SHA1.