To calculate the amount of hemodialysis ultrafiltration, the first step is to determine the patient’s dry weight, which is the ideal target weight at the end of dialysis when the patient is completely edema-free and feels particularly comfortable. After determining the dry weight, the patient should be weighed before each dialysis session, and the amount of ultrafiltration for each dialysis session should be calculated by subtracting the dry weight from the weight weighed before dialysis. However, it is also important to note that it is best not to exceed 5% of the dry weight for each dialysis session. If it exceeds 5%, complications such as hypotension may occur during the dialysis process, causing discomfort to the patient, so it is important to control the amount of water intake between dialysis sessions.