Blood oxygen & tattooed skin
Has anyone else found their Apple Watch blood oxygen monitor will not work on tattooed skin?
Apple Watch Series 8
Question marked as
Permanent or temporary changes to your skin, such as some tattoos, can also impact heart rate sensor performance. The ink, pattern, and saturation of some tattoos can block light from the sensor, making it difficult to get reliable readings. For more info, see the 'What else affects your heart rate reading' section in:
Get the most accurate measurements using your Apple Watch - Apple Support