Light Meter turns your phone into an accurate lux meter and foot candle meter. Using your device's ambient light sensor, it gives you instant, stable illuminance readings in lux (lx) or foot-candles (fc) — no expensive light measuring hardware needed.
Whether you're checking grow lights for your plants, dialing in photography lighting, or making sure your workspace meets recommended light levels, this lux light meter gives you a clear reading in seconds.
HOW IT WORKS
Place your phone where you want to measure light and open the app. The light meter instantly displays the current illuminance along with live minimum and maximum values. Tap HOLD to freeze a reading, and reset min/max whenever you start a new measurement.
KEY FEATURES
✓ Real-time lux meter readings from the ambient light sensor
✓ Switch units between lux (lx) and foot-candles (fc)
✓ HOLD button to freeze the current light measurement
✓ MIN / MAX tracking for every session
✓ Diffuser support (paper or professional diffuser) for more accurate readings
✓ Manual calibration (−20% to +20%) with Indoor, Outdoor and Studio profiles
✓ Camera overlay so you can see exactly what you're measuring
✓ Measurement smoothing for steady, readable values
✓ Multi-language support
SPECIALIZED MODES (PRO)
🌱 Plant mode — approximate PAR readings for grow lights, greenhouses and indoor gardening
📷 Photography mode — evaluate studio and scene lighting before you shoot
💼 Workspace mode — check office, desk and task lighting against recommended lux levels
MEASUREMENT HISTORY & CSV EXPORT (PRO)
Save your light measurement sessions automatically, review trends over time, and export everything to CSV for reports, lighting audits or documentation.
GUIDED CALIBRATION (PRO)
Every phone's light sensor behaves a little differently. Guided calibration walks you through matching your readings against a reference, so your lux meter stays as accurate as possible on your specific device.
WHO IS THIS LIGHT METER FOR?
• Plant lovers and growers — verify your grow light setup delivers enough light (PAR) for healthy plants
• Photographers and filmmakers — balance studio lighting and check exposure conditions
• Architects, electricians and facility managers — measure illuminance for lighting audits and compliance checks
• Anyone at home or work — test whether your reading lamp, desk or room lighting is bright enough
TYPICAL ILLUMINANCE LEVELS
• 50 lux — living room mood lighting
• 300–500 lux — office and desk work
• 1,000 lux — detailed tasks and workshops
• 10,000+ lux — daylight outdoors
ACCURACY NOTE
Readings come from your device's built-in light sensor, so accuracy varies between phone models. Use the calibration tools and diffuser modes to improve precision. This app is a practical measuring tool, not a replacement for certified professional instruments.
Download Light Meter now and measure light like a pro — free.
Lux meter with plant PAR, photography & workspace modes. Measure light in lux/fc