Piano Key Cleaner

Steps

1. Close the fallboard (key cover) and dust the top surface with a dry cloth first. Open it and visually inspect the keys for any stuck-on debris, stains, or discoloration.
2. Mix 2 drops of mild dish soap into 1 cup of distilled water. Stir gently — you want a barely sudsy solution, not a bubbly one.
3. Dip a lint-free cloth into the solution and wring it out thoroughly. The cloth must be only slightly damp. Squeeze it until no water drips when you press firmly.
4. Clean the white keys first. Wipe each key individually from the back (near the fallboard) toward the front edge — never side to side. Side-to-side wiping pushes moisture into the gaps between keys where it can reach the wooden key mechanism underneath.
5. Work in groups of 5-6 keys at a time. After wiping each group, immediately dry them with a separate clean cloth using the same front-to-back motion.
6. For stubborn stains on white keys, dampen a cotton swab with the cleaning solution and apply gentle targeted pressure on the stain. Avoid scrubbing, which can wear the key surface.
7. Switch to a fresh cloth for the black keys. Black keys are typically made of ebony (on older pianos) or molded plastic, and residue from white key surfaces should not be transferred to them.
8. Wipe each black key from back to front, just as you did with the white keys. Use less moisture on black keys — ebony especially is sensitive to water absorption.
9. Use dry cotton swabs to clean the narrow channels between adjacent keys where dust and skin cells accumulate. Insert the swab gently and wipe along the side of each key without forcing it deep into the keybed.
10. Leave the fallboard open for 15-20 minutes to allow any residual moisture to evaporate before closing it.

Why It Works

Piano keys accumulate a combination of skin oils, dead skin cells, sweat, dust, and sometimes food residue from players’ hands. This buildup is slightly acidic (from sweat’s lactic acid and amino acids), which over time etches the surface of both plastic and ivory keys, making them look dull and feel sticky. A tiny amount of dish soap acts as a surfactant, reducing water’s surface tension so it can lift and suspend these oils and particles rather than just pushing them around. Distilled water is critical because tap water contains dissolved minerals (calcium, magnesium, iron) that leave white residue as the water evaporates, which is particularly visible on black keys. The front-to-back wiping direction is not merely a preference — it follows the natural gap geometry of a piano keyboard, where keys are widest at the front and tightest at the back, preventing moisture from being channeled into the mechanical action.

Tips

• Clean piano keys monthly if the piano is played daily. For occasional-use pianos, every 2-3 months is sufficient.
• To determine whether your piano has ivory or plastic keys, look at the key surface under a light at an angle. Ivory has a visible grain pattern and a slightly warm, matte texture. Plastic keys are perfectly smooth and uniform. Ivory keys also have a visible seam line where the key head meets the key tail.
• Yellowed ivory keys cannot be whitened with cleaning alone. The yellowing is caused by UV exposure oxidizing the keratin protein in ivory. A piano technician can buff ivory keys to reduce yellowing, but home remedies (toothpaste, baking soda, lemon juice) do more harm than good.
• Keep the fallboard closed when the piano is not in use. UV light from windows is the primary cause of key discoloration on both ivory and plastic.
• Maintain 40-60% relative humidity in the room. Pianos are primarily wood instruments, and humidity swings cause far more damage than dirty keys ever will. If you hear notes going out of tune frequently, the humidity is the likely culprit.
• Never use disinfecting wipes (Clorox, Lysol) on piano keys. The quaternary ammonium compounds and bleach in these products degrade plastic surfaces and destroy ivory.