Free tools · No signup
Construction calculators
Field-fast calcs the bot inside Forward runs over text. We ship the same logic here as a no-signup web tool because they’re useful on their own, and because making them public is the lowest-friction way for a foreman to see if the texting product would fit their workflow.
Electrical · NEC 310.16
NEC wire size calculator →
Pick the smallest conductor that carries your load per NEC Table 310.16. Handles the termination-temperature rule (NEC 110.14(C)) correctly.
Electrical · NEC 215.2 / 210.19
Voltage drop calculator →
Check any branch or feeder against the NEC 3% / 5% rule. Single-phase + three-phase, copper + aluminum, full conductor cmil table.
Mechanical · ASHRAE / IECC
HVAC load estimator →
BTU/h cooling + heating from area, exposure, and climate zone. Quick rule-of-thumb sanity check before a Manual J load calc.
Concrete · Takeoff
Concrete volume calculator →
Cubic yards for a slab, footing, column, or wall. Built-in waste-factor — the part most online calculators leave out.
Structural · IBC serviceability
Beam deflection calculator →
Mid-span deflection of a simply supported beam under uniform load. Steel + wood presets. L/360 + L/240 IBC checks.
Drywall · Takeoff
Drywall sheet calculator →
Count 4×8, 4×10, or 4×12 sheets for a wall + ceiling area, with the real-world waste factor field foremen actually use.
Code check · IBC / IRC
Stair rise + run code check →
Verify a stair rise/run against IBC 1011 (commercial) or IRC R311 (residential). Blondel's Rule comfort check included.
Paint · Takeoff
Paint coverage calculator →
Gallons of paint for an area, with two-coat default + primer toggle. Smooth / textured / porous substrate coverage rates.
Concrete · Rebar
Rebar linear feet calculator →
LF of rebar for a slab, wall, or footing — one-way or two-way mat, with on-center spacing and waste-factor inputs.
Structural · AISC ASD
Bolt allowable shear calculator →
Single/double shear allowable for A325, A490, A307 bolts at common diameters. AISC ASD basis.
Plumbing · Pipe sizing
Pipe size for GPM calculator →
Smallest pipe diameter that carries a target flow rate under velocity ceilings (copper hot/cold, steel, PVC).
Plumbing · Storage
Water heater sizing →
Storage tank size for commercial spaces by occupancy + use (office / multifamily / restaurant / school / healthcare).
Electrical · Service
Transformer kVA sizing →
Smallest standard transformer kVA rating that handles your connected load with NEC 1.25 continuous-load factor applied.
HVAC · Ductwork
Duct size for CFM →
Smallest round duct diameter (and equivalent rectangular size) that carries a target CFM under a chosen friction-loss rate.
Plumbing · Demand
Fixture units → GPM →
Hunter's Curve conversion from WSFU to peak demand GPM. Flush-tank + flush-valve system types.
Masonry · Takeoff
CMU block count →
Standard 8×8×16 block count for a wall, with the 5-10% waste factor masons actually use.
Masonry · Takeoff
Brick count →
Modular, standard, or king-size brick count for a face area. Built-in waste factor.
Electrical · Emergency power
Generator sizing →
Generator kW + kVA from running load and motor-start surge, with load factor + 65% surge-handling rule.
Electrical · NEC 220
Panel demand load (NEC 220) →
Service / panel demand kVA + amps via NEC 220 standard method with the 100% / 35% / 25% demand-factor brackets baked in.
Flooring · Takeoff
Tile count →
Tile count for an area at any tile dimension. Waste factor adjustable per pattern (square / diagonal / mosaic).
Accessibility · ADA 405
Ramp slope ADA check →
1:12 slope check + 30-inch-per-run rise check per ADA 405 / IBC 1012. Pass/fail with landing-requirement reminder.
Safety · OSHA 1926
OSHA fall protection threshold →
6/10/15-ft threshold check for construction, scaffolding, and steel erection per OSHA 29 CFR 1926.
Framing · Takeoff
Joist count →
Floor / ceiling joist count at 12-24 inch OC spacing, plus rim joists and blocking-row estimate.
Framing · Takeoff
Stud count →
Wall stud count at 16 or 24 inch OC, with adjustable percentage for openings + bracing.
Built by Forward
Forward runs these calcs over text from inside your project.
Forward is a phone number your field crew texts. It reads from Procore, Autodesk Construction Cloud, and OneDrive, runs the same NEC + IBC + IMC + IPC calcs you see above, and replies with cited answers in seconds. RFIs, drawings, submittals, change orders, daily logs — no app, no login.