PAR Meter: Grow Light PPFD DLI

PAR Meter is a quantum meter that measures the light your plants actually use: PPFD (Photosynthetic Photon Flux Density) and DLI (Daily Light Integral) over the whole day. Choose your plant type and see at once whether the light intensity is too weak, right or too strong, and what to do about it.

KEY FEATURES
🌱 PPFD in µmol/m²/s, the photon flux at the canopy right now
📅 DLI in mol/m²/day, the total light over a day, from your light period (photoperiod)
🌻 Plant type selection with recommended DLI and PPFD ranges shown as a green, yellow and red band on the gauges
👍 Plain-language guidance: too weak, right or too strong, and whether to move the lamp, dim it or change the hours
💡 Light source types: LED grow light, daylight, household white LED, fluorescent (T5, CFL), HPS, metal halide (MH), ceramic metal halide (CMH), or your own µmol per lux factor
☀️ Illuminance in lux and foot-candles, so it also works as a lux meter
⏸️ Hold button to freeze the reading
💾 Save measurements with timestamps and comments, and export them
🔧 Built-in advanced calibration for extra accurate readings
📱 Uses the phone's ambient light sensor, no camera needed (phones without a light sensor use the camera)

WHY MEASURE GROW LIGHT?
Lux and lumens measure light as our eyes see it, not as plants use it. Plants grow on PAR, Photosynthetically Active Radiation, the light between 400 and 700 nm that photosynthesis can use. A lamp can look bright and still deliver little usable light. Measuring PPFD lets you hang your grow lamp at the right height, find the dark corners of your grow tent, check how much sunlight a windowsill gets, find low light and shade spots for indoor plants, and compare one grow light with another. With a plant type selected, the app also recommends how many hours per day the light should be on.

PLANT TYPES WITH RECOMMENDED LIGHT LEVELS
🌿 Houseplants, foliage and flowering: pothos, monstera, philodendron, ficus, peace lily, African violet
🌸 Orchids, phalaenopsis and bromeliads
🌵 Succulents, cacti, aloe and jade plants
🌱 Seedlings, cuttings, clones and propagation
🥬 Microgreens, leafy greens, lettuce, spinach and kale
🌿 Herbs: basil, mint, parsley, coriander, rosemary
🥕 Root vegetables: carrots, beets, radishes, potatoes
🍓 Fruits and berries: strawberries, blueberries, citrus
🍅 Fruiting vegetables: tomatoes, peppers, chili, cucumbers, eggplant
🌳 High-light plants, vegetative and flowering stages

IDEAL FOR
🏠 Indoor gardening: grow tents, grow rooms, windowsills and balconies
🏡 Gardens, greenhouses, hydroponics, aquaponics and vertical farming
🐠 Planted aquariums, terrariums and vivariums
🌲 Bonsai, carnivorous plants and rare houseplants
💡 Comparing LED grow lights, quantum boards and COB lamps
📐 Mapping a grow area and setting the lamp height above the canopy
🎓 Horticulture, botany and agriculture education

FREE TO USE
Measuring PPFD, DLI and lux under daylight and white LED is free, with no time limit and no ads. The other light source types, saving measurements and calibration are available with a one-time fee or subscription, still at a fraction of the cost of a dedicated PAR meter.

SUPPORT & FEEDBACK
Your feedback helps improve the app. Contact us at apps@contechity.com for support or suggestions.

Turn your phone into a grow light meter today and give your plants the light they need.