# Builder's Formulator — Calculations for Builders > Professional construction calculator with extensive formulas and reference materials. (iPhone/iPad app by Historycentral.com.) - Source: https://appshunter.io/ios/app/builders-formulator/id306247596 (this page in markdown: same URL + `.md`) - Developer: [Historycentral.com](https://appshunter.io/developer/1744330560) - Category: Business, Productivity - Price: Free with in-app purchases - Rating: 2.00/5 from 3 App Store ratings · 6 written reviews indexed - Age rating: 4+ - Requires: iOS 26.4 · 48 MB - Languages: American English - Released: 2009-02-28 - Data updated: 2026-08-23 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/builders-formulator/id306247596/reviews.md ## What is Builder's Formulator? Builder's Formulator is the ultimate professional reference tool for general contractors, builders, plumbers, HVAC technicians, and electricians. With over 2,600 formulas, 136 plumbing code charts, 27 technical drawings, and complete ADA accessibility references, it's the most comprehensive construction calculator available. CONSTRUCTION — Calculate joists, studs, headers, hardwood flooring costs, concrete and excavation volumes, bricks needed for a wall, roofing materials, stair dimensions, lumber requirements, and acoustic absorption. Includes material weight references for dozens of building materials. STRUCTURAL ENGINEERING — Comprehensive beam analysis for single-span and cantilevered beams with point loads, uniform loads, and triangular loads. Concrete design for flexure, shear, axial compression, and prestressed concrete. Masonry stress analysis, steel design, wood design, flat plate calculations, soil bearing capacity, and road/highway formulas. ELECTRICAL — Calculate kilowatts, horsepower, efficiency, power factor, watts, amps, resistance, and voltage. Includes transformer calculations, voltage drop analysis, motor sizing, battery calculations, AC/DC circuits, Ohm's Law, impedance, frequency conversions, and UPS sizing. PLUMBING & HVAC — Pipe sizing, flow velocity, friction loss, pressure calculations, drainage and venting, storm drainage, gas piping, water heater sizing and recovery, pump horsepower, septic and sewage systems, grease interceptors, thermal expansion, water supply sizing, medical gas piping, and swimming pool calculations. Boiler efficiency, condensation, and comprehensive water flow analysis. HVAC SYSTEMS — Dedicated ductwork and duct sizing, fan laws, pump laws, gas laws, hydronic formulas, psychrometrics, ventilation rates, heating design, refrigeration, steam systems, air change rate equations, humidity calculations, and heating/cooling load analysis. FINANCIAL — Mortgage calculations, depreciation, investment analysis, interest formulas, debt ratios, and price quotes. REFERENCE LIBRARY — 136 plumbing code charts and tables covering gas piping, drainage, venting, backflow prevention, medical gas, thermal expansion, fixture units, and more. 27 technical drawings for venting systems, chimney terminations, gas clearances, and water heater installations. Complete ADA accessibility reference with 52 diagrams and 17 documents covering wheelchair dimensions, grab bars, ramps, parking, elevators, and restroom clearances. Plus built-in reference tables for occupancy loads, brick sizes, lumber dimensions, wire gauge, concrete mixes, and insulation R-values. CONVERSIONS — Hundreds of unit conversions across pressure, volume, linear measure, area, weight, flow, power, BTU, and eight temperature scales including Celsius, Fahrenheit, Kelvin, and Rankine. FEATURES — Save and revisit calculations, mark favorites for quick access, toggle between US and metric units, export and share results, and view your complete calculation history. Dark mode interface designed for jobsite readability. Builder's Formulator — one app for every trade on the job. ## Key features - Over 2,600 formulas - Plumbing code charts - Technical drawings - ADA accessibility references - Unit conversions - Save and revisit calculations - Mark favorites ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Builder Pro | $2.99 | one-time | ## Recent user reviews (6 of 6) All indexed reviews: https://appshunter.io/ios/app/builders-formulator/id306247596/reviews.md ### 1/5 — WHAT-A-WASTE *2010-02-20* DON'T WASTE YOUR TIME NOR MONEY.... ### 1/5 — Disappointing *2009-07-23* More of a toy than a tool! ### 3/5 — its getting beter *2009-06-03* It should have a formula for box fill (how big of a box you need for how many wires) ### 3/5 — Uhm! *2009-04-26* I can tell a carpenter didn't consult on the design. I wish there was a way to enter tape measure readings to decimal feet. Example. 15' 3-1/16th" to 15.xx feet. When figuring concrete and building it is vital to be accurate down to the 100th and some cases further. I would also like to have the option to covert back and forth from feet inches yards psi on screen so I wouldn't need to change formulas. It is a good start and can be handy in the future. Good thing I have a carpenter calc in my bag. With the right tuning this could be a great tool on the job. Also the way the numbers are displayed can be confussing for me. But then again it could be converting from decimal feet back to tape measurements and calling it back over the radio for the saw man or the office can make it hard to use for me. If I could do it all in my head I wouldn't need the app in the first place! ### 1/5 — Lacking a lot *2009-03-24* The other reviewers say it all. For a 9.99 application I expected a lot more. Will not calculate amps of a 1phase 3000w circuit. A lot of frankly useless formulas that a typical contractor/builder will never need or use. Perhaps there will be improvements in future updates. ### 1/5 — I'm kicking myself! *2009-03-01* The format stinks. It's mostly full of unorginized and repetitive conversions. ## Frequently asked questions about Builder's Formulator ### What types of calculations does Builder's Formulator offer? Builder's Formulator offers a wide range of calculations including construction, structural engineering, electrical, plumbing, HVAC, and financial formulas. It also includes unit conversions and ADA accessibility references. ### How many formulas are included in Builder's Formulator? Builder's Formulator includes over 2,600 formulas to assist professionals in various construction-related fields. This extensive library covers many specialized calculations. ### Does Builder's Formulator have ads? No, Builder's Formulator does not contain advertisements. It is a free application designed to provide an uninterrupted professional reference experience. ### What reference materials are available in Builder's Formulator? The app features 136 plumbing code charts, 27 technical drawings, and complete ADA accessibility references with diagrams and documents. It also includes built-in reference tables for various construction materials and standards. ### Can I save my calculations in Builder's Formulator? Yes, you can save and revisit your calculations within Builder's Formulator. You can also mark frequently used formulas as favorites for quick access. ### What is the user rating for Builder's Formulator? Builder's Formulator has a user rating of 2.0 stars based on 3 ratings. This indicates a mixed reception from its current user base. ### Is Builder's Formulator available on multiple devices? Builder's Formulator is supported on iPhones and iPads, making it accessible for professionals on the go. It is designed for Apple's mobile operating systems. ### How often is Builder's Formulator updated? The latest version of Builder's Formulator is 4.0, which was last updated on April 7, 2026. This suggests a recent update with new features or improvements. ## Version history (last 5 releases) ### 4.1 — 2026-08-11 Expanded handling of metric calculations ### 4.0 — 2026-04-07 --- What's New in Version 5.0 Completely rebuilt from the ground up. Builder's Formulator has been rewritten with an entirely new codebase, delivering a faster, more modern experience. Massive formula expansion — Now includes over 2,600 formulas, up from 200. Every calculation from our Electrical, Carpentry, and Plumbing Formulators is here, plus hundreds more. New: Structural Engineering — Full beam analysis for single-span and cantilevered beams, concrete design, masonry, steel, wood design, flat plates, soils, and road calculations. New: HVAC Systems — Dedicated section with ductwork sizing, fan laws, pump laws, gas laws, hydronic formulas, psychrometrics, ventilation rates, heating design, refrigeration, and steam system calculations. New: Expanded Plumbing — Pipe sizing and friction loss, drainage and venting, storm drainage, gas piping, septic systems, grease interceptors, thermal expansion, water supply, medical gas piping, and swimming pool calculations. New: ADA Reference Library — 52 accessibility diagrams and 17 reference documents covering wheelchair clearances, grab bars, ramps, parking, elevators, restrooms, and more. New: Technical Drawings — 27 plumbing and mechanical drawings for venting systems, chimney terminations, gas clearances, and water heater installations. New: Plumbing Code Charts — 136 charts and tables covering gas piping, drainage, venting, backflow prevention, medical gas, fixture units, thermal expansion, and sewage disposal. New: Reference Tables — Built-in lookup tables for occupancy loads, brick sizes, lumber dimensions, wire gauge, concrete mixes, and insulation R-values. US & Metric toggle — Switch between US and SI units across all calculators. Favorites & History — Star your most-used formulas and access your complete calculation history. Dark mode interface — Designed for readability on the jobsite. ### 3.1 — 2012-10-10 iPhone 5 Compatible, iPad Retina compatible, dozens of additional formulas ### 3.0 — 2011-10-24 Support for ePrint, Airplay, additional metric formulas and iOS 5 compatibility. ### 2.8 — 2011-04-29 iPad Native, 200 new conversion formulas, New Electric formulas. New Metric formulas ## More apps by Historycentral.com - [Finance Formulator](https://appshunter.io/ios/app/finance-formulator/id294194640) - [Personal Formulator](https://appshunter.io/ios/app/personal-formulator/id296173495) - [Electrical Formulator](https://appshunter.io/ios/app/electrical-formulator/id299749412) - [Plumbing Formulator](https://appshunter.io/ios/app/plumbing-formulator/id303497783) - [Carpentry Formulator](https://appshunter.io/ios/app/carpentry-formulator/id305583131) All apps by Historycentral.com: https://appshunter.io/developer/1744330560 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-23.*