Grower Tools

Showing 12 calculators

Updated

VPD Calculator

Dial in temperature and humidity for peak transpiration. Includes interactive heatmap and growth-stage targets.

Environment Humidity
Free

Electricity Cost Calculator

Estimate daily, monthly, and annual kWh costs per device. Supports time-of-use rates and live recalculation.

Cost Energy
Free

BTU / AC Sizing Calculator

Size your air conditioner from heat loads — lights, equipment, people, and infiltration.

Cooling Environment
Free

Dehumidifier Sizing Calculator

Calculate pints per day needed for grow rooms and drying rooms. Covers plant transpiration and infiltration.

Humidity Environment
Free

CO₂ Calculator

Dial in enrichment rates, runtime, and tank size. Shows ppm rise curve from ambient to target.

CO₂ Environment
Free

Humidifier Sizing Calculator

Size humidifier output (L/hr and PPD) to reach your target RH from current conditions.

Humidity Environment
Free

Ventilation & Carbon Filter

Calculate required CFM with losses for filters, ducting, bends, and pressure drop.

CFM Odor Control
Free

PPFD / Light Coverage

Match fixtures to canopy size with PPFD averages and DLI. Includes top-down coverage heatmap.

Lighting DLI
Free

Pump & Irrigation Flow

Size GPM/LPM vs. static head, emitters, and pipe friction. Three tools in one: emitter, pump, and tubing.

Irrigation Hydro
Free

Nutrient Mixing & Dilution

Mix stock to target EC/PPM and batch size. Includes EC target, label rate, and C1V1 dilution tools.

Nutrients EC / PPM
Free

Yield Estimator & Planner

Estimate dry yield, g/W, g/ft², and harvest timeline. Includes animated Gantt chart and strain modifiers.

Planning Harvest
Free

CEA ROI Calculator

Estimate margin, ROI, and payback period for commercial grows. Multi-year projection with break-even chart.

ROI Commercial
How to use this calculator hub

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Use the search box or category pills to find the right tool quickly.

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Tap any card — every tool is mobile-friendly, free, and copy-ready.

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Frequently Asked Questions

Are all these grow room calculators free to use?+
Yes — all 12 calculators are completely free. No account or signup is required. They work on any device including phones and tablets, and results can be copied or shared via URL.
Which calculator should I start with?+
Start with the VPD Calculator to dial in your environment, then the Electricity Calculator to understand costs. If sizing a new room, run BTU/AC, Dehumidifier, and Ventilation together to size all your environmental equipment at once.
Are the calculator formulas accurate?+
Yes — all 12 calculator formulas have been independently audited for accuracy. The tools use standard industry formulas including the Magnus equation for VPD, Hazen-Williams for pump head loss, and psychrometric equations for humidity calculations.

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