Abstract: A method for determining a property of a fiber suspension comprises obtaining a sample and diluting the sample by a first dilution, thereby providing a diluted sample, while retaining essentially all of the sample, and mixing the diluted sample, thereby providing a mixed, diluted sample. By removing part of the mixed, diluted sample and retaining an amount of the mixed, diluted sample, further diluting the mixed, diluted sample by adding dilution water to the retained amount of the mixed, diluted sample, thereby providing a further diluted sample, while retaining essentially all of the mixed, diluted sample, mixing the further diluted sample, thereby providing a mixed, further diluted sample, and repeating these steps until the concentration is suitable for measuring the property of the further diluted sample, this property can be measured with high accuracy. A device for determining a property to be determined of a suspension is also provided.