There are many factors that can contribute to your weight. A few of the obvious ones are your height, body fat percentage, and muscle mass. Weight can also fluctuate a bit during the day due to water retention. If you are retaining a lot of water, the scale may show that you are a few pounds heavier than normal. For this reason, you should weigh yourself in the morning to get the most accurate measurement. To get even more accurate, weigh yourself a few mornings in a row and take the average.
Many people ask the question — how much should I weigh? There are BMI calculators all over the internet, but you should use discretion when using them. They only account for your height and weight, and do not factor in muscle mass. If you have above average muscle mass, these calculators might actually indicate that you are overweight even though you are in great shape and have a lot of muscle.
Use this chart to get an estimate of how much you should weigh based on your height and weight: