Tattoos Can Disrupt Fitness Tracker Sensors, Research Confirms

Executive Briefing

• Reveals that tattoo ink blocks light-based PPG sensors, causing inaccurate or absent heart rate readings on wearables.
• Shows wrist-detection sensors may fail on tattooed skin, forcing users to repeatedly unlock their devices.
• Confirms a 2025 study found tattoo interference varies by activity level, with greatest inaccuracy recorded at rest.
• Highlights workarounds including repositioning the device, using chest straps, or applying epoxy stickers over sensors.
• Notes light-based sensors also underperform on darker skin tones, signaling a broader inclusivity gap in wearable R&D.