General biology reference and utility calculators. Browse our free general biology tools below — all calculators are instant, accurate, and require no sign-up.
Annealing Temperature Calculator — Calculate optimal PCR primer annealing temperature using nearest-neighbor thermodynamics, basic Tm formulas, and salt-adjusted methods for reliable amplification.
Cricket Chirp Thermometer Calculator — Estimate outdoor temperature from cricket chirp rates using Dolbear's Law. Convert chirps per minute to Fahrenheit and Celsius with species-specific adjustments.
Dry Matter Calculator — Calculate dry matter intake, percentage, and feed conversion for livestock and pet nutrition. Compare feeds on dry matter basis for accurate diet formulation.
Feed Conversion Ratio Calculator — Calculate feed conversion ratio (FCR) for poultry, swine, cattle, and aquaculture. Track feed efficiency, cost per gain, and compare across species and production stages.
Growing Degree Units Calculator — Calculate growing degree days (GDD/GDU) for corn, wheat, and other crops. Track heat accumulation, predict crop staging, and plan planting dates.
Grain Bin Calculator — Calculate grain bin capacity in bushels for round and flat-bottom bins. Estimate stored volume, peak grain height, and weight for corn, wheat, soybeans, and more.
Grain Conversion Calculator — Convert between bushels, pounds, metric tons, and hundredweight for corn, wheat, soybeans, and 10+ grain types. Includes price and volume unit conversions.
Ligation Calculator — Calculate optimal insert-to-vector molar ratios for DNA ligation reactions. Determine DNA mass, moles, and volumes for cloning with T4 DNA ligase.
Livestock Fence Calculator — Calculate fencing materials, posts, wire, and cost for livestock enclosures. Supports barbed wire, electric, woven wire, and board fence for cattle, horses, and sheep.
Llama Calculator — Calculate llama weight, feed requirements, body condition scoring, stocking rate, and shearing yield. Complete management tool for llama and alpaca owners.
Log Reduction Calculator — Calculate microbial log reduction, percent kill, and surviving organisms for sterilization, disinfection, water treatment, and food safety applications.
MLVSS Calculator — Calculate mixed liquor volatile suspended solids, SRT, F/M ratio, and sludge age for activated sludge wastewater treatment process optimization.
Mulch Calculator — Calculate mulch volume in cubic yards, number of bags, and cost for garden beds, landscaping, and tree rings. Supports multiple mulch types and bed shapes.
Mowing Cost Calculator — Calculate lawn mowing time, fuel usage, and cost for residential and commercial properties. Compares walk-behind, riding, and zero-turn mowers with labor estimates.
Pet Sitter Rates Calculator — Calculate pet sitting rates for dogs, cats, and exotic pets. Estimate daily, overnight, and boarding costs with regional adjustments and service add-ons.
Rat Cage Calculator — Calculate minimum cage size for pet rats based on number of rats. Includes cage dimensions, bar spacing, shelf area, and recommended cage models.
Vapor Pressure Deficit Calculator — Calculate VPD from temperature and humidity for greenhouse, indoor garden, and cannabis growing. Includes crop-specific optimal ranges and leaf temperature correction.
Vegetable Yield Calculator — Estimate vegetable garden yield by crop, area, and growing conditions. Plan harvest quantities for family gardens, market farms, and community plots.
Wastewater Treatment Calculator — Calculate wastewater treatment parameters including BOD removal, hydraulic retention time, sludge age, and activated sludge design for treatment plants.
Water Potential Calculator — Calculate plant water potential from solute concentration, pressure, and matric components. Predict osmotic potential using van't Hoff equation for biology students.