Free online tools for engineers & designers
Handy calculators that run right in your browser — no download and no account needed. Built by the Mahelak BIM team.
Revit & BIM
Check, preview and set up Revit files and project standards. 9 tools
Revit Version Checker
See which Revit version saved an RVT or RFA file, without opening Revit.
- Batch check .rvt, .rfa, .rte and .rft
- Files never leave your computer
- Compare with your Revit version
- Copy results as CSV
Revit Build Numbers
Every Revit update since 2015, and which one you have.
- Paste a build from Help > About
- All 2015 to 2027 updates
- See how many updates you are behind
- Copy the list as CSV
BIM Workflow Guide
Step-by-step Revit project setup for your discipline and team.
- Architecture, structure or MEP
- Solo, team, local or cloud
- Linking, coordinates and Copy/Monitor
- Printable checklist to sheets
RFA Family Viewer
Preview a Revit family and read its types and parameters without Revit.
- Preview image, category and version
- Types and parameters as a table
- Batch of files, nothing uploaded
- Export CSV or a type catalog
Family Parameter Generator
Shared parameters, type catalogs and a Revit script from one table.
- Shared parameter file with GUIDs
- Type catalog .txt
- Python script for Revit 2022+
- Door, window and MEP presets
Revit Keyboard Shortcuts
Search, edit and export Revit keyboard shortcuts.
- Every default shortcut, searchable
- Edit keys with conflict warnings
- Import and export KeyboardShortcuts.xml
- Printable cheat sheet
Fill Pattern Generator
Design hatch patterns and download a .pat file.
- 11 presets, tiles to herringbone
- Revit model or drafting patterns
- Millimetres or inches
- Live preview, copy or download
ISO 19650 File Naming
Build and check file names to the UK National Annex.
- Field-by-field generator
- Validator with clear fixes
- Numbered series and CSV
- Type and role code lists
RAL to RGB
RAL Classic colours as HEX and RGB for Revit materials.
- All 216 RAL Classic colours
- Nearest RAL from any HEX
- Revit-ready RGB values
- Copy with one click
MEP
Lighting, power, cooling, air and water calculations. 5 tools
Lighting Calculator
Plan fixture layouts to reach your target lux.
- Target lux (auto) or manual layout
- Utilization & maintenance factors
- 2D plan and 3D view
- DXF export for CAD / Revit
Voltage Drop Calculator
Size cables by voltage drop and current rating.
- 1-phase, 3-phase and DC
- Copper or aluminium, PVC or XLPE
- IEC 60228 / IEC 60364-5-52 data
- Recommended cable size
AC Size Calculator
Cooling load and the right AC size for any room.
- Quick estimate or detailed heat gain
- BTU/h, tons, kW and HP
- Moderate, hot or very hot climate
- Recommended split unit size
Duct Size Calculator
Size ducts by equal friction or velocity.
- Round, rectangular and flat oval
- L/s, m³/h or CFM
- EN 1506 and inch sizes
- Velocity and aspect ratio checks
Water Pipe Size Calculator
From fixture units to peak flow and pipe size.
- Fixture units from IPC tables
- Copper, PPR, PEX and steel
- Hazen–Williams friction
- Pressure left at the fixture
Construction
Quantities, costs, concrete, stairs and unit conversions for site work. 6 tools
Quantity Takeoff Calculator
Quantities for the whole building from its dimensions.
- Concrete and estimated rebar
- Brick, block and AAC walls
- Plaster, paint, tiles and ceilings
- BOQ in PDF, Excel and CSV
Construction Cost Estimator
Building cost per m² or a priced bill of quantities.
- Any currency, your own prices
- Shell to fully finished
- Quick or detailed BOQ estimate
- PDF and Excel with formulas
Material Takeoff
Estimate building material quantities for any room.
- Tiles, paint, bricks & blocks
- Door, window, beam & column deductions
- Brick, mortar and paint settings
- Export CSV or print a BOQ
Concrete & Rebar Calculator
Concrete volume, mix materials and rebar weight.
- Slabs, footings, columns, beams, stairs
- Cement bags, sand, gravel and water
- Common site mixes and 1:2:4 ratios
- Rebar weight and 12 m cut list
Stair Calculator
Work out risers, treads and pitch, with code checks.
- IBC 2021, IRC 2021 or custom limits
- 2R + T comfort check
- Millimetres or feet-inches
- Scaled side section
Unit Converter
Convert AEC units, including Revit-style feet-inches.
- Feet-inches to 1/64"
- Force, pressure, flow and power
- Slope as %, degrees or 1:n
- Every unit at once
Architecture
Sheets, scales, accessibility and building code checks. 4 tools
Paper Size Viewer
Visualize and compare standard drawing sheet sizes.
- ISO A & B, ANSI and ARCH series
- mm, cm and inches
- Compare and overlay sizes
- CAD text-height guide
Drawing Scale Calculator
Find the scale that fits your drawing on the sheet.
- ISO A, ARCH and ANSI sheets
- Margins and title block
- 1:n and feet-inch scales
- Text height and DIMSCALE
Ramp & Parking Calculator
Accessible ramps, car park ramps and parking layouts.
- ADA ramp slope, landings and rails
- Car park ramp transitions
- Parking at 90°, 60°, 45° and 30°
- Accessible stall count
Occupant Load Calculator
IBC occupant load, egress width and number of exits.
- Every IBC Table 1004.5 factor
- Fixed seats, benches and booths
- Egress width and exit count
- ft² or m²
Guides & free resources
How to calculate lux for a room
The lumen method explained step by step, with a worked office example.
Free BIM standards & guides
19 free PDFs: BIM execution plans, AEC (UK) standards and LOD specifications.
Need a Revit family or BIM tool?
Browse 3,300+ ready-made Revit families, or ask us to build something custom.