Free Calculators

Arithmetic, geometry, quantity, and planning tools with visible methods and limits — no signup, instant results. Higher-risk tools remain unavailable until their sources, logic, and test cases are verified.

89 CalculatorsMethods & limits shown

89 calculators shown.

ADA Accessible Route WidthFree

Bounded walking-surface width check vs ADA 2010 §403.5.1

ADA Elevator RequirementFree

Bounded car dimensions vs ADA 2010 Table 407.4.1

Allowable Building AreaFree

IBC 2024 Equation 5-1 + Table 506.3.3 frontage factor

Annual Heating DemandFree

Completed model result ÷ matching area vs verified target

Architecture FeeFree

Construction cost + complexity → design fee and phase breakdown

Convert m², ft², acres, hectares, mi² — exact factors

Beam DeflectionFree

Max elastic deflection vs L/240, L/360, L/180

Bearing CapacityFree

General bearing equation (Vesic) → qu and allowable qa

Wall area + brick size + joint → bricks per m²/ft² and total

Brick Bond PatternFree

Verified layout rate → allowance and pack-rounded order

Building Site EUIFree

Building type + area → Energy Use Intensity vs ASHRAE 90.1 benchmark

California ADU FeeFree

ADU size + primary dwelling area → state impact-fee threshold and proportional factor

California ADU HeightFree

Verified ADU path + transit/site facts → bounded California minimum height limit

California ADU ParkingFree

Verified exemption facts + bedrooms → California parking exemption or local cap

California ADU PermitFree

Verified receipt date + milestone conditions → bounded statutory planning date

California ADU SetbackFree

Verified project path + Coastal Zone status → bounded California setback baseline

California ADU SizeFree

Verified legal path + unit facts → bounded California state size comparison

Circuit Breaker SizeFree

Verified loads and factor → bounded entered-rating comparison

Cleanroom HVAC SizingFree

ISO 14644 air changes per hour → supply airflow

Commercial Electrical Load CalculatorFree

Verified demand-load schedule → total VA and arithmetic line current

Concrete Curing TimeFree

Verified strength and curing records vs project requirements

Concrete Stairs VolumeFree

Steps + waist slab geometry → concrete volume (m³ / yd³)

Condensation RiskFree

Temp + RH → dew point and surface condensation risk

Construction CostFree

Building type + size + location → cost range by system (RSMeans)

Cooling LoadFree

Envelope + solar + people + ventilation → BTU/h & tons

Curved Slab Concrete VolumeFree

Ring / arc slab geometry → concrete volume (m³ / yd³)

Daylight FactorFree

Window area + room geometry → daylight factor per BS 8206

Drawing ScaleFree

Convert drawing ↔ real length at any metric or imperial scale

Drywall Finish LevelFree

Wall segments + finish level (L0–L5) → labor hours, board count, material + bid total

Duct SizingFree

Equal-friction → round diameter, velocity, rectangular

Embodied Carbon by MaterialFree

Σ (mass × A1–A3 factor) → cradle-to-gate kgCO₂e

Energy DemandFree

Completed model needs ÷ matching reference area

Excavation VolumeFree

Pit dimensions + swell → bank and loose (haul) volume

Exit Sign SpacingFree

Corridor length + viewing distance → signs needed

Lot area + entered FAR → FAR-derived floor area

FAR / DensityFree

Lot area + entered FAR + user assumptions → transparent planning scenario

Fillet Weld SizeFree

Specified leg ÷ user-verified required fillet-weld leg

Greywater System SizingFree

Verified supply vs demand and engineered storage

Heating LoadFree

Envelope transmission + infiltration → design heating load

Hospital Construction CostFree

Hospital type + GFA or bed count → cost estimate per m² and bed

Hotel Construction CostFree

Hotel class + GFA or key count → cost estimate per m² and key

IBC 2024 Egress CapacityFree

Capacity-based width only; component minimums remain a separate check

IBC 2024 Occupant LoadFree

Three governed functions of space → bounded model-IBC occupant-load preview

IBC 2024 Plumbing FixtureFree

Occupant load + selected actual use → bounded IBC 2024 Table 2902.1 fixture counts

IBC Required ExitsFree

Space vs story scope → bounded exit-count preview; unsupported cases fail closed

IBC Travel DistanceFree

Separate Group B travel, common-path, and dead-end model-code limits

Imperial to MetricFree

Length, area, mass, volume — convert all units at once

Irrigation Flow RateFree

GPM + area → precipitation rate and run time

Kitchen Hood Airflow CheckerFree

Scheduled airflow vs verified listed/design requirement

Material DensityFree

Searchable kg/m³ + lb/ft³ for 40+ building materials

Moment of InertiaFree

Section dimensions → Ix, Iy, area, section modulus S, radius of gyration r

Office Construction CostFree

Office class + SF + location → cost range by structural system

Room size + openings → net wall area and gallons of paint

Parking Supply ScenarioFree

Verified local or demand ratio + project quantity → transparent parking scenario

Passive House CriteriaFree

Selected PHPP/test values vs verified project criteria

Skin friction + end bearing → Qu and allowable Qa

Property TaxFree

Market value × assessment × mill rate → annual tax

R-Value ↔ U-ValueFree

Convert thermal R and U between SI and imperial units

Rainwater HarvestingFree

Catchment + rainfall → annual harvestable yield

Rebar Development LengthFree

Available embedment ÷ user-verified ACI-required length

Rebar Mat QuantityFree

Slab + spacing → bars each way, linear length, and weight

Residential Construction CostFree

Home type + size + finish level → cost per SF estimate

Retail Construction CostFree

Retail type + size → base shell and tenant improvement cost ranges

Rise + run → pitch (x:12), angle, slope multiplier, rafter length

Roof U-ValueFree

Insulation + layers (upward flow) → roof U-value

Sabine RT60Free

Room volume + surface absorption coefficients → RT60 per Sabine formula

Sand VolumeFree

Area + depth → loose sand volume, weight, and bulk bags

School Construction CostFree

School type + GFA or seat count → cost estimate per m² and seat

Slope / GradientFree

Rise + run → percent grade, ratio, angle, and inclined length

Slope Stability Factor of SafetyFree

Analyzed factor ÷ user-verified project criterion

Solar Heat GainFree

Window area · SHGC · orientation → peak solar gain (BTU/h)

Solar PaybackFree

Cost − incentives ÷ savings → payback period

Spray Foam CoverageFree

Area + thickness → board feet, R-value, and sets to order

Stair HeadroomFree

Check clearance vs IBC §1011.3 / IRC 80" (spiral 78")

STC RequirementsFree

Bounded IBC residential target or verified project target → documented rating comparison

Steel Column LoadFree

Same-basis axial demand ÷ verified governing strength

Steel Connection Bolt CountFree

AISC 360-16 direct-shear limit state → bounded lower-bound bolt count

Structural Depth-to-SpanFree

Preliminary member depth (ACI minimums + rules of thumb)

Structural LoadFree

User-entered tributary area, repeated levels, loads, and factors → transparent totals

Thermal BridgeFree

Linear heat loss (Ψ·L·ΔT) + fRsi mould-risk check

Transformer SizingFree

Load (kW/kVA/amps) → required kVA + standard rating

Trench VolumeFree

Length, depth, widths → trench excavation volume (trapezoidal)

Assembly layers → overall U-value and R-value per ISO 6946

Voltage DropFree

NEC Ch.9 Table 9 effective-Z method, 3%/5% check

Wall Assembly U-ValueFree

Layer build-up (ISO 6946) → assembly R and U-value

Window Size for DaylightingFree

Room depth + target daylight factor → minimum glazing area

Window U-ValueFree

Glass + frame + edge → whole-window Uw (ISO 10077)

Wire AmpacityFree

Verified table value + factors + termination cap → bounded ampacity comparison

Wood ConnectionFree

Hankinson formula → allowable bearing at any grain angle