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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 CO₂ enrichment needs, tank duration, and cost
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Related: VPD Calculator
💨Find the right dehumidifier size for your grow space
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Related: VPD Calculator · Reservoir
Calculate precise salt weights for any hydroponic nutrient formula
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Related: Feed 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
💧Calculate pH up/down doses for your reservoir
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Related: Nutrient Calculator · Reservoir
📅Generate a week-by-week feeding schedule with EC and pH targets
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Related: Nutrient Calculator · EC/PPM Converter
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