BuildCalc vs Span Calc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
BuildCalc
This app enhances traditional construction calculators with advanced functions for layout, material estimation, and complex calculations. It offers interactive features, customizable material sizes, and streamlined results presentation to reduce complexity and improve accuracy for professionals.
- Advanced baluster and stair layout
- Fence post and material estimation
- Interactive calculation adjustments
- Customizable material sizes
- Miter saw vs. protractor rafter calculations
- Streamlined results display and saving
Read full descriptionHide full description
What if you could take the best construction calculator and fix it. That’s right ... you love it, it has served you well, and you stand by it ... but could it do more? Could it be easier to use? After testing by pros from around the world, BuildCalc is ready to give you more - more function and more answers with less complexity, less hassle, and less confusion. MORE FUNCTIONALITY: • Advanced Baluster Function: Complete layout of railing and staircase balusters with less guess work - and with all the flexibility you need for every custom job. • Advanced Stair function: Stair layouts for professional results - including dimensioned drawings of your Stringer, Stringer Installation, and Finished Staircase. And you can email a PDF of these drawings right from BuildCalc so you can print them or share them. • Fence Function: Give BuildCalc a fence row length and it will tell you how many posts, rails, pickets, and or panels you need. • Interactive Functions: The Stair, Baluster, Compound Miter, and Rafter functions are now fully interactive. Want to change input values? Change the Run? Switch between Regular and Irregular Hip Roof analysis? You can do this and your results will be updated automatically - without you needing to remember what key to press. MORE ANSWERS: • You are no longer tied down to: only one brick, block or tile size for the masonry function; a fixed number of drywall sheet sizes; only one footer cross sectional area; or one size of shingles and sheathing. If you don’t see the size you want, you can add as many as you need. And for area input, you can store your custom sizes in Length x Width format, so you won’t have to do mental gymnastics to figure out what was the dimensions for that last size you stored. • Want to cut your hip roof rafter using a miter saw ... or a circular saw using a hand-held protractor? With a tap of a button, BuildCalc will automatically switch between Miter Saw and Protractor results. BuildCalc can do this for Compound Miters, too. • Sheathing Angles, Purlin Angles, Gable Area, Backing Angles, Plan Angles, Rough vs. Finished Stair Layout Dimensions, Stringer Throat, Stringer installation dimensions ... and a lot more not found on other construction calculators. LESS COMPLEXITY AND LESS HASSLE: • Tired of having to press and press and press buttons to get the results of a calculation? BuildCalc puts an end to this. For all advanced functions, you get ALL of your results in list form with just one or two key taps. • And, rather than having to write down those results, all advanced functions allow you to save your results - as many times as you want with a label you choose - so you can recall the complete results at your convenience. Now you can do a calculation today and two days, two weeks or two years later, it is there for you. • Less “quirks”. Have you been annoyed by arcane key stroke sequences on other construction calculators? We are too. BuildCalc 2.1 streamlined the keystrokes to do a better job of giving you less “errors” and more results. Don’t remember what you have to enter before a Hip Rafter or Stair calculation? Well, now you don’t have to. BuildCalc will provide you with a check list of inputs and on-the-spot help to get it right. • Drywall and Masonry “Room Mode”: If you have stored a Length, Width and Height for a room, BuildCalc will give you the Drywall or Masonry required for the walls and the ceiling / floor - with only a tap of the Drywall or Masonry button. No more pondering over complex key sequences ... it just works. NOW WITH ADVANCED STAIRS, BALUSTER, AND HIP/VALLEY FUNCTIONS Get more results than you ever could before - including dimensioned Stringer, Stringer Installation and Finished Staircase Drawings. Drawings can then be emailed to others or printed at your convenience. Email us and we'll send you an example!
Span Calc
Calculate maximum horizontal spans for wood joists and rafters using various lumber species and grades. Compares multiple options for common loading conditions based on NDS® standards.
- Calculates joist and rafter spans
- Supports all softwood and hardwood lumber
- Uses 2021 NDS® for Wood Construction
- Compares multiple species and grades
- Handles common loading conditions
Read full descriptionHide full description
The American Wood Council (AWC) Span Calculator for Wood Joists and Rafters (Span Calc) performs calculations for all species and grades of commercially available softwood and hardwood lumber as found in the 2021 National Design Specification® (NDS®) for Wood Construction. Joists and rafter spans for common loading conditions can be determined. A span options calculator allows selection of multiple species and grades for comparison purposes. Supported by the Softwood Lumber Board. Maximum horizontal spans for joists and rafters are calculated based on the following assumptions and conditions: · Joists and rafters are oriented to support vertical loads applied to the narrow (1.5 in. thick) face of the member, resulting in strong-axis bending. · At least three joists or rafters are installed parallel to one another and spaced not more than 24 inches on-center, with properly designed sheathing attached on the top (compression) edge of each joist or rafter. · Joists and rafters are single-span with adequate structural support at each end. The Span Calculator does not address cantilevered joists and rafters, multiple-span joists and rafters, or spliced joists and rafters. · For joists and rafters, most building codes specify a minimum bearing length of 1.5 inches on wood or metal and not less than 3 inches on masonry or concrete. These minimum bearing lengths are to be used in the absence of calculated bearing lengths. Consult the local building code for specific requirements. · Joists and rafters carry only combinations of dead load plus live load (D + L), dead load plus snow load (D + S), or dead load plus roof live load (D + Lr). The Span Calculator does not address wind load or seismic load. · Buildings in regions with ground snow loads greater than 70 psf should not use the prescriptive provisions of the governing building code without approval of the authority having jurisdiction. Buildings in these high snow zones should be designed in accordance with accepted engineering practice. While every effort has been made to insure the accuracy of the information presented, and special effort has been made to assure that the information reflects the state-of-the-art, neither the American Wood Council nor its members assume any responsibility for any particular design prepared from this Span Calculator application. Those using this Span Calculator assume all liability from its use.
Screenshots
Verdict
The clearest difference is review sentiment: BuildCalc at 87% against Span Calc's 30%. BuildCalc also leads on rating (4.7 vs 2.9) and chart position (#67 vs unranked). Span Calc's advantage is price (Free vs $24.99) and update cadence (every 10 days vs every 3 weeks). On ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Span Calc is free to download; BuildCalc costs $24.99 up front. Neither carries in-app purchases, so what you see is what you pay.
BuildCalc holds the better App Store score, 4.7 against 2.9. Both are backed by a comparable volume of ratings — 72 and 15 respectively. Written reviews point the same way: 87% of BuildCalc's written reviews are positive against 30% of Span Calc's.
BuildCalc ships an update every 3 weeks, Span Calc every 10 days. The most recent releases landed on October 11, 2026 and October 12, 2026 respectively.
| Parameter | BuildCalc | Span Calc |
|---|---|---|
| Price | $24.99 | Free — better |
| Rating | 4.7 (72 ratings) — better | 2.9 (15 ratings) |
| Positive reviews | 87.4% of reviews — better | 29.6% of reviews |
| Number of ratings | 72 — better | 15 |
| Update frequency | Every 3 weeks | Every 10 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Best chart rank | #67 — better | — |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 14.2 — better |
| Further details — not scored | ||
| Size | 15 MB | 168 MB |
| Age rating | 4+ | 17+ |
| Developer | 42nd Parallel | American Wood Council |
Customer experience
BuildCalc
Span Calc
In-app purchases
BuildCalc
No in-app purchases
Span Calc
No in-app purchases
Questions
Is BuildCalc free?
Is Span Calc free?
Which has better reviews, BuildCalc or Span Calc?
Do BuildCalc or Span Calc have ads?
Which is updated more often, BuildCalc or Span Calc?
Other comparisons















