When was the last time you cleaned your washing machine? It may sound odd to clean a machine that's built to clean things, but washing machines can get really (really) gross. One study found that bacteria like salmonella and E-coli is often present in washing machines—and can leech onto what you think are your freshly washed clothes. Read on for a quick how-to!

Step 1: Run a Hot Cycle with Vinegar

Run an empty, regular cycle on hot, using two cups of vinegar instead of detergent. White vinegar will not damage clothes. The hot water-vinegar combo removes and prevents bacteria growth. Vinegar can also act as a deodorizer and will cut through mildew odors.

Step 2: Scrub the Inside and Outside

In a bucket or nearby sink, mix about ¼ cup vinegar with a quart of warm water. Use this mixture, plus a sponge and dedicated toothbrush, to clean the inside of the machine. Pay special attention to soap and other dispensers, the inside of the door and if you have a front-loading washing machine, the rubber seal. (If your soap dispenser is removable, soak it in the vinegar water before scrubbing.) Give the machine's exterior a quick wipe down, too.

Step 3: Run a Hot Cycle

Run one more empty, regular cycle on hot, without detergent or vinegar. You should clean your washer every six months to prevent bacteria and mineral build up, and to make sure your clothes are actually clean when they come out of the washer.