Calculators
Mushroom cultivation calculators
Free tools for the math you actually need: substrate ratios, spawn rate, grain hydration, and yield. Sign up free to run live calculations and save results to your grows.
Substrate
Bulk substrate ratios and PF Tek mixes.
BRF PF Tek Calculator
Scale the classic 2:1:1 PF Tek jar recipe to any number of jars and any jar size. Outputs total and per-jar amounts.
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Coir Brick Hydration Calculator
Enter your coir brick weight and get the exact water volume, expanded volume, and hydrated weight for any monotub or grow-bag batch.
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CVG Substrate Calculator
Get exact coir, vermiculite, gypsum, and water amounts for any CVG bulk substrate batch. Adjust the ratio and hydration to match your tek.
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Manure-Based Substrate Calculator
Get exact composted-manure, coir, vermiculite, gypsum, and water amounts for any dung-loving species batch.
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Master's Mix Substrate Calculator
Get exact hardwood pellet, soybean hull, and water weights for any Master's Mix batch. Tune the ratio for your species.
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Spawn
Grain spawn rate and hydration math.
Grain Hydration Calculator
Get exact soak water, simmer water, and timings for any grain spawn batch. Pick your grain, enter dry weight, and prep with confidence.
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Spawn-to-Bulk Calculator
Match grain spawn weight to any bulk substrate batch. Pick a ratio (1:1 through 1:4) and see colonization-time tradeoffs side by side.
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Lab
Sterile work and culture prep math.
Harvest
Yield analysis and biological efficiency.
Biological Efficiency Calculator
Calculate biological efficiency (BE %) from your fresh harvest and dry substrate weights, then benchmark it against typical bands for your species.
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Mushroom Yield Estimator
Predict your fresh harvest from a batch — honest low / mid / high range by species and flush count.
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