AWC Connection Calc vs CRSI Rebar Reference
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
AWC Connection Calc
Calculate capacities for various fasteners in wood connections, including single bolts, nails, and screws. Supports lateral and withdrawal capacities for wood-to-wood, wood-to-concrete, and wood-to-steel connections based on 2024 NDS standards.
- Calculate single bolt, nail, lag screw, and wood screw capacities
- Determine lateral (single and double shear) capacities
- Calculate withdrawal capacities
- Supports wood-to-wood connections
- Supports wood-to-concrete connections
- Supports wood-to-steel connections
- Based on 2024 NDS standards
Read full descriptionHide full description
Provides users with a mobile approach to calculating capacities for single bolts, nails, lag screws and wood screws per the 2024 NDS. Both lateral (single and double shear) and withdrawal capacities can be determined. Wood-to-wood, wood-to-concrete, and wood-to-steel connections are possible. LIMITS OF USE SCOPE AND LIMITATIONS Connection capacities are calculated on the basis of design provisions in the 2024 National Design Specification® for Wood Construction (NDS®). The calculated capacities are based on the following assumptions and conditions: · Bolts and lag screws must meet the requirements of ANSI/ASME B18.2.1, wood screws must meet the requirements of ANSI/ASME B18.6.1, and nails must meet the requirements of ASTM F1667. · Bolts, lag screws and wood screws must be installed in predrilled lead holes in accordance with the provisions of NDS Chapter 11. · Bolts, lag screws and wood screws must not be forcibly driven into connection members with a hammer or other impact device. · The faces of adjacent connection members are brought into contact when fasteners are installed. · Adequate edge distances, end distances and spacing must be provided for all fasteners to prevent splitting of wood connection members, in accordance with NDS Chapter 11. · Steel side plates with thickness of ¼ in. or greater must meet the requirements of ASTM A36, and steel side plates with thickness less than ¼ in. must meet the requirements of ASTM A653, Grade 33. · Concrete connection members must have compressive strength (fc') of at least 2500 psi. · The on-line Connection Calculator does not specifically address multiple-fastener connections. See NDS Chapters 10-11 and NDS Appendix E for applicable design provisions. · The on-line Connection Calculator does not address fasteners installed at an angle to grain (e.g., toe-nails). See NDS Chapters 10-11 for applicable design provisions. · The on-line Connection Calculator does not address fasteners subjected to combined lateral and withdrawal loading. See NDS Chapters 10-11 for applicable design provisions. · The on-line Connection Calculator does not address connections with gaps or non-structural spacer blocks between members. GENERAL STRUCTURAL GUIDELINES The quality of structural wood products and fasteners and the design of load-supporting members and connections shall conform to provisions of the NDS. The on-line Connection Calculator is based on design equations for lateral loading and withdrawal loading specified in NDS Chapters 10 and 11, along with fastener characteristics specified in NDS Appendix L. The NDS Commentary, NDS Appendices I through N, and NDS Chapters 12-13 provide additional guidelines regarding the design of connections in wood structures. RESPONSIBILITY FOR DESIGN 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 on-line Connection Calculator. Those using this on-line Connection Calculator assume all liability from its use. This Connection Calculator is not meant to be a replacement for the NDS and does not encompass all of its design options. The American Wood Council On behalf of the industry it represents, AWC is committed to ensuring a resilient, safe and sustainable built environment. To achieve these objectives, AWC contributes to the development of sound public policies, codes and regulations that allow for the appropriate and responsible manufacture and use of wood products. We support the utilization of wood products by developing and disseminating consensus standards, comprehensive technical guidelines and tools for wood design and construction, as well as providing education regarding their application. Contact AWC via email: info@awc.org or connect with one of AWC’s regional building code experts.
CRSI Rebar Reference
Access essential data for reinforcing bars (rebar) including specifications, hook details, and marking requirements. This app serves as a quick reference for industry standards and links to online resources.
- ASTM standard reinforcing bar specifications
- Standard hook details (90, 135, 180 degrees)
- Stirrup/tie hook details
- ASTM reinforcing bar marking requirements
- Minimum yield and tensile requirements
- Links to CRSI online resources
Read full descriptionHide full description
QUICK REFERENCE! This ready reference app from the Concrete Reinforcing Steel Institute is a handy desk and field resource and includes information on ASTM standard reinforcing bars (rebar), standard hook details, standard stirrup/tie hook details, and ASTM reinforcing bar marking requirements. The app provides standard rebar specifications including sizes, diameters, areas and weights along with 90-, 135- and 180-degree hook details. Minimum yield and minimum tensile requirements per ASTM are also included. Industry standard bar markings for inch-pound rebar is illustrated for grades 40, 50, 60, 75, 80, 100 (A615), 100 (A1035), and 120. Links to the CRSI’s online resources are included.
Screenshots
Verdict
The clearest difference is rating: CRSI Rebar Reference at 3.3 against AWC Connection Calc's 2.5. CRSI Rebar Reference also leads on ads (none vs shown) and review sentiment (33% vs 17%). AWC Connection Calc's advantage is in-app purchases (none vs 3) and update cadence (weekly vs every 5 weeks). On price, device support and iOS requirement 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
Both are free to download. CRSI Rebar Reference sells 3 one-off in-app purchases. AWC Connection Calc asks for nothing beyond the download.
CRSI Rebar Reference holds the better App Store score, 3.3 against 2.5. That said, the two scores are not equally well evidenced: CRSI Rebar Reference has 16 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 17% of AWC Connection Calc's written reviews are positive against 33% of CRSI Rebar Reference's.
AWC Connection Calc ships an update weekly, CRSI Rebar Reference every 5 weeks. The most recent releases landed on June 7, 2026 and June 1, 2026 respectively.
| Parameter | AWC Connection Calc | CRSI Rebar Reference |
|---|---|---|
| Price | Free | Free |
| Rating | 2.5 (2 ratings) | 3.3 (16 ratings) — better |
| Positive reviews | 16.7% of reviews | 33.3% of reviews — better |
| Number of ratings | 2 | 16 — better |
| Update frequency | Weekly — better | Every 5 weeks |
| Ads | Yes | No — better |
| In-app purchases | No — better | Yes |
| Monetization | Ad-supported | Free — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 14.2 — better | 15.1 |
| Further details — not scored | ||
| Size | 156 MB | 51 MB |
| Age rating | 17+ | 17+ |
| Developer | American Wood Council | Concrete Reinforcing Steel Institute |
Customer experience
AWC Connection Calc
CRSI Rebar Reference
In-app purchases
AWC Connection Calc
No in-app purchases
CRSI Rebar Reference
- CRSI - Rebar Identifier Module$2.99
- CRSI Development Length ACI$4.99
- CRSI Development length AASHTO$4.99
Questions
Is AWC Connection Calc free?
Is CRSI Rebar Reference free?
Which has better reviews, AWC Connection Calc or CRSI Rebar Reference?
Do AWC Connection Calc or CRSI Rebar Reference have ads?
Which is updated more often, AWC Connection Calc or CRSI Rebar Reference?
Other comparisons















