Free grower calculators
Fast, no-signup calculators for hydroponic and soil growers — built on Truleaf's peer-reviewed plant data. Bookmark them, or link to them from your own guides.
NPK Nutrient CalculatorGet target N-P-K in ppm plus the elemental mass to dose per reservoir, by crop and growth stage.Open toolEC ↔ ppm ConverterConvert electrical conductivity to TDS/ppm and back, on the 500, 640, or 700 scale.Open toolFrost-Zone Seed-Starting CalculatorTurn your last-frost date or USDA zone into exact indoor-sow, transplant, and direct-sow dates.Open tool
All tools are free, require no account, and run entirely in your browser. Educational estimates — always verify against your own meters and local conditions.