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Sit down in a chair where you can easily put both of your feet flat on the floor. Then, extend either your left or right leg straight out in front of you. Make sure your foot is relaxed when your leg is extended all the way. Roll your ankle a few times and point your toes and flex them back and forth to get your foot in a true relaxed state. Unless you are very flexible, it is difficult to get an accurate measurement on your own. Have another person take a tape measure or ruler and measure from the bottom of your heel to where the ball of the foot bends at the end of the ball. The measurement they get is your ideal heel height. The ball of the foot is the padded part of the sole that is between your arch and toes. If you rise up off of your heels, you will be balancing on the balls and toes of your feet. If you don’t have someone who can help you measure, you can do it on your own. Attach a tape measure to the wall at the same height your leg will be extended. Attaching it where the bottom of your heel will be is ideal for the easiest and most accurate measurement. Set up a camera against a wall at a height where it will be able to fully capture your extended leg and tape measure. You will need a camera with a self-timer, selfie stick, or remote to capture the picture. Take a few test shots to make sure you have the camera set to the right angle and height. Once you’ve taken a good photo, you can determine the measurement on the camera screen, but it’s typically easier if you upload the photo onto your computer. After it has been uploaded, you can zoom in to determine your ideal heel height or draw lines with Photoshop or a similar image editing software to make determining the measurement very easy to read.

Summary:
Sit and extend your leg directly in front of you. Have a friend measure from the ball of your foot to your heel. Attach measuring tape to the wall alternatively. Set up a camera to capture the measurement on your own. Upload the photo and draw lines to determine heel height.