Don�t be embarrassed to show your bathroom to your guests! Grout can really get dirty in a very short time, but it is rather simple to get it looking white again. There are many products in the market to clean grout and tile. They usually contain bleach, to restore the original color of the material. The best thing to do is to seal the grout from the beginning, to avoid the collection of water in it, and then keep the tile clean on a regular basis. You can also make a paste of hydrogen peroxide and baking soda and apply it to the grout with an old toothbrush. Let the paste sit for around an hour and then rinse it out. Bleach is the best remedy for dark grout. Brush it onto the grout and watch it turn white!