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12 free tools for indoor gardeners. Calculate VPD, nutrients, pH, lighting, and more. No account required.
Calculate vapor pressure deficit for optimal plant transpiration
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Related: DLI Calculator · Dehumidifier Sizing
Calculate daily light integral from PPFD and photoperiod
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Related: PPFD Map · Light Sizing
Calculate PPFD, watts per square foot, and optimal hanging height
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Related: PPFD Map · DLI Calculator
Visualize light distribution across your canopy with an interactive heatmap
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Related: DLI Calculator · Light Sizing
Calculate precise salt weights for any hydroponic nutrient formula
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Related: Nutrient Schedule · EC/PPM Converter · pH Calculator
Convert between EC, PPM-500, PPM-700, and TDS-442 scales
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Related: Nutrient Calculator · Reservoir
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