Abstract: A method and apparatus for performing rounding in a data processor (10). In one embodiment, two instructions are used to implement a procedure for rounding operands of finite but arbitrary precision. A first instruction "rndp" performs a preliminary rounding operation by analyzing bits which are less significant than the rounding point and updating the values of the round (RND) and sticky (STK) status bits (70, 71) in a defined manner. A second instruction "rnd" performs the rounding of the most significant portion of the operand, using the contents of the RND and STK status bits (70, 71) as determined by the one or more iterations of the "rndp" instruction. By appropriate use of these two instructions, and additional add-with-carry operations, an operand of any length may be rounded at an arbitrary point using a data processor (10) with fixed width registers (40) and a fixed width ALU (30).