A piano needs to be tuned regularly to maintain its sound quality and pitch. Over time, the strings inside the piano will naturally change tension. When this happens, a piano tuner will add or remove tension to the strings, which raises or lowers the pitch accordingly. Regular piano tuning ensures that the instrument sounds its best and remains in good condition.

The two most common ways to tell if a piano needs to be tuned are: (1) the piano sounds off-key or out of tune, and/or (2) the piano has not been tuned in over a year.

Alternatively, when a piano is moved from one location to another it will need tuning.

It's generally recommended that you have your piano tuned at least once a year. However, the frequency of tuning can depend on factors such as usage, climate, and the general age and condition of the piano. If you play your piano frequently, it may need to be tuned more often than once a year. Professional pianists and music schools, for example, may have their pianos tuned every 2-3 months. On the contrary, for pianos that are not played as often, you may only want to get their piano tuned every 6-12 months. Regardless of how often the piano is played, it is not recommended to let a piano go more than 1 year without tuning.

Yes, however, when a piano hasn't been tuned in years, the tension on the strings may have changed so significantly that the piano is very far out of tune. In such cases, the piano may require several tunings in order to bring the strings up to the correct pitch.

While regular tuning can help prevent more significant problems down the line, here are some tips to help you maintain your piano in between tunings:

• Regularly dust and clean your piano's exterior with a soft cloth. Avoid using any cleaning products that contain harsh chemicals that could damage the finish.

• Keep your piano away from windows and direct sunlight, and use a humidifier or dehumidifier to maintain a consistent humidity level. Fluctuations in temperature and humidity can affect the tuning and overall condition of your piano.

• Be careful when moving the piano. If you need to move your instrument between floors or across locations, it's best to hire professional movers who specialize in moving pianos.

The length of time a piano stays in tune after a tuning can vary depending on several factors, including the quality and condition of the piano, how often it is played, and the environment in which it is located. In general, most pianos will stay in tune for several months after a tuning, but it's not uncommon for some notes to start to sound out of tune after a few weeks. Here are some things to keep in mind about maintaining your piano’s pitch:

• If you play your piano frequently, the strings may stretch more quickly, causing the piano to go out of tune faster.

• Fluctuations in temperature and humidity can cause a piano to go out of tune. If the environment in which the piano is located is not consistent, it may go out of tune more quickly.

• Older pianos or pianos that have not been well-maintained may go out of tune more quickly than newer, well-maintained pianos.