AllCalc - Field Calculator

AllCalc puts 80 professional trade calculators in your pocket. Built for HVAC technicians, electricians, plumbers, construction workers, auto mechanics, GSE technicians, and network techs who need fast, accurate answers on the job.
Works completely offline. No internet required. No ads. No account needed.
GENERAL (6 tools): Scientific calculator with memory and history, unit converter (temperature, length, weight, volume, area, speed, pressure, energy), time calculator, date calculator, percentage calculator, tip calculator.
CONSTRUCTION (12 tools): Construction Master calculator (modeled after the CM5/4020 with feet-inches-fractions, right triangle, stud count, area, circle, and advanced arc/rake/hip/block functions), polygon room area calculator with scaled SVG drawing, area calculator with visual, volume calculator with 3D visual, concrete and material estimator (bag counts, water, weight for concrete/sand/topsoil/gravel), lumber calculator with board feet + wall framing + deck framing modes, stair calculator (IRC compliant), roof pitch, paint and drywall estimator, flooring/tile calculator, floor load calculator, soil and fill volume.
HVAC (9 tools): Psychrometric calculator, airflow and duct sizing, heat load estimator, mixed air temperature (OA/RA linked), U-value and heat loss, hydronic piping, refrigerant pressure-temperature charts (R-410A, R-22, R-134a, R-407C, R-454B, R-32), fan laws, ASHRAE 62.1 ventilation.
ELECTRICAL (13 tools): Power/watts/BTU converter, amp and wire sizing (NEC Table 310.16), voltage drop calculator, conduit fill, Ohm’s law, transformer sizing, motor reference table (1/6 to 125 HP), lighting load (LED/fluorescent with circuit count), EV charger load, generator sizing, energy cost calculator with appliance lookup, motor sizing (torque/load/speed), solar panel calculator with ITC payback.
PLUMBING (6 tools): Pipe flow (Hazen-Williams), pipe pitch and slope, water heater sizing, pump sizing (WHP/BHP/motor), water pressure calculator (PSI/head/static/friction), fixture unit calculator (IPC/UPC with Hunter’s curve).
AUTO / GSE (11 tools): Tire size comparison with speedometer error, coolant mix calculator, fuel economy (MPG/trip cost/vehicle comparison), engine displacement, gear ratio and speed, battery and charging (charge time/runtime/CCA), hydraulic cylinder (force/flow/speed), OBD-II code reference (55+ codes), belt and pulley calculator, torque converter (ft-lb/N-m/in-lb/kg-cm), compression ratio.
NETWORK (9 tools): Subnet/CIDR calculator, PoE power budget planner, bandwidth and transfer time, cable distance and loss (Cat5e-Cat8/coax/fiber), common ports reference (50+ ports including BACnet/UniFi/MQTT), Ethernet cable pinout (T568A/B/crossover), VLAN planner, WiFi channel reference (2.4 + 5 GHz with DFS), IP address converter.
REFERENCE (13 tools): R-values and insulation, pipe sizes, wire gauge table (AWG), drill bit and tap chart, bolt torque specs, IP address ranges, wire color codes, ASHRAE climate zones, lumber dimensions (nominal vs actual), seasonal planting guide, how-to guide, O-ring sizes (AS568), thread pitch reference (UNC/metric/NPT with tap drills).
Features: Dark and light themes, adjustable text size, accent color picker, haptic feedback with adjustable intensity, favorites system to pin your most-used tools, fully offline operation with embedded fonts, responsive design for phones and tablets.