Comparison

Fastener Calc vs iAlignTest

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Fastener Calc

This app provides engineers, technicians, and students with essential tools for bolted joint development. It includes converters for various units and geometrical and mechanical calculators for dimensioning and design in joining technology.

Highlights
  • Unit converters (length, torque, pressure, force)
  • Metric-imperial fastener conversion
  • Drill hole size calculator
  • Tapping screw pilot hole design
  • Bolt size and property class estimation
  • Disc spring calculator
  • Thread engagement length calculator
Features
Read full description

Bossard - Proven Productivity Bossard calculators and converters are designed for engineers, technicians, designers and students involved in the development and assembly of bolted joint. Calculators categories: * Converters are used for converting different units of measure, such as lengths, hardnesses, pressures etc. The converters are divided into topic areas to enable the most efficient selection possible. --- Length converter is used for converting more than 68 different units of measure, such as inch, centimetre, metre, mile, foot, yard etc. --- Torque converter is used for converting different torques, such as newton metre, dyne metre, kilogram force metre, ounce force inch etc. --- Pressure converter is used for converting different pressure units, such as bar, millibar, psi, pascal etc. --- Force converter is used for converting different force units, such as newton, dyne, kilogram force, ounce force etc. --- Metric - imperial units fasteners converter. Converting between metric and inch fasteners forces you to make compromises.This converter gives you best proposals and will show you the differences in an easy way. --- Hardnes converter. Conversion of hardness-to-hardness or hardness-to-tensile-strength values for unalloyed and low-alloy steels and cast iron. * Geometrical calculators are used for dimensioning and implementation in the joining technology. --- Drill hole size for tapped threads. Calculate the proper tap drill size for the most commonly used screws. --- Pilot hole design for tapping screws. Calculate core hole diameters for tapping screws (Based on DIN 7975:1989) --- Pilot hole design for ecosyn®-Plast. Calculate the boss geometry for various types of thermoplastics for ecosyn®-plast. --- Tolerances for shafts and holes. Find and calculate tolerances for holes and shafts. Based on standard tolerance classes and limit deviations from ISO 286-2:2010 * Mechanical calculators are used for dimensioning and designing in the joining technology. --- Estimation of bolt size and property class. Which dimension and strength should a bolt have for my application? Estimate the required diameter and property class. Based on VDI 2230:2014. --- Disc spring calculator. Calculate disc springs with geometry and properties according to DIN 2093. Calculations based on DIN 2092. --- Cost savings calculator. Calculate savings potential for fasteners by looking at activity costs. --- Thread engagement length calculator. Calculate the theoretical minimum required thread engagement length for blind hole and through hole applications. Based on VDI 2230:2014 --- Torque and preload with nut factor. Calculate tightening torque and preload with nut factor for inch screws. Based on formula T = D*K*F. --- Torque and preload with nut factor and tool accuracy - imperial system. Calculate tightening torque and preload with nut factor for inch screws. The calculation considers tool accuracy and scatter on preload. --- Torque and preload with nut factor and tool accuracy - metric. Calculate tightening torque and preload with nut factor for metric screws. The calculation considers tool accuracy and scatter on preload. Based on formula T = D*K*Fmean --- Torque and preload with friction scatter. Calculate tightening torque and preload for hex head and socket head screws. The calculation considers friction scatter, tool accuracy and scatter on preload. Based on VDI 2230:2014 --- Torque and preload for customized geometry and material. Calculate tightening torque, preload and surface pressure for hex head, socket head and countersunk screws. Customized head shapes, hole chamfers, reduced shanks and materials are available options. Based on VDI 2230:2014 --- Torque and preload calculator. Calculate tightening torque, preload and surface pressure for hex head and socket head screws. Based on VDI 2230:2014.

About

iAlignTest

Features
Read full description

An interactive reference tool for machine shaft alignment. It provides the common reference tables, specifications and charts for shaft alignment tolerance. Three main standards are included: 1- NASA Precision Alignment Specs (Ames Policy Directive APD 8830.1) 1.a) Alignment Tolerance for Soft Foot 1.b) Alignment Tolerance for Short Coupling: Horizontal and Angular 1.c) Alignment Tolerance for couplings with spacers 2- Common Tolerance Table with the RPM input for Angular, Parallel, and Spacer Shaft cases User selects the RPM range, enters alignment values and sees the alignment condition and tolerance range for the machine. 3- Interactive Alignment Tolerance Chart with three regions: Excellent, Acceptable, and Unacceptable. User enters RPM, offset and angles in both horizontal and vertical directions, and interactively sees the condition of the machine in the chart Features: - Shaft Alignment Specification: NASA Standard - Interactive Shaft Alignment Tolerance Table - Interactive Shaft Alignment Tolerance Chart in mm and inch - Email the results DISCLAIMER: iAlignTest is intended for educational purposes. Although the references in this App are made with great care, however it may contain errors and inaccuracies. Using the results of this App is the responsibility of the user.

Screenshots

Fastener Calc3 screens
iAlignTest4 screens

Verdict

The call

The clearest difference is price: iAlignTest at Free against Fastener Calc's $2.99. Fastener Calc's advantage is update cadence (every 4 months vs every 32 months) and iOS requirement (8.0 vs 15.0). 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

CostPrice · In-app purchases · Ads · Monetization

iAlignTest is free to download; Fastener Calc costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Fastener Calc ships an update every 4 months, iAlignTest every 32 months. The most recent releases landed on October 20, 2026 and October 14, 2026 respectively.

Scorecard3 real differences · 7 level
Fastener Calc versus iAlignTest: the parameters behind the verdict, then further details
ParameterFastener CalciAlignTest
Price$2.99Free — better
Rating1.0 (1 ratings) — better—
Positive reviews0.0% of reviews—
Number of ratings1 — better—
Update frequencyEvery 4 months — betterEvery 32 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS8.0 — better15.0
Further details — not scored
Size8 MB8 MB
Age rating4+4+
DeveloperBossard AGMotionics LLC

In-app purchases

None

Fastener Calc

No in-app purchases

None

iAlignTest

No in-app purchases

Questions

Is Fastener Calc free?
Fastener Calc costs $2.99, with no in-app purchases.
Is iAlignTest free?
iAlignTest is free to download, with no in-app purchases.
Do Fastener Calc or iAlignTest have ads?
Neither Fastener Calc nor iAlignTest shows ads.
Which is updated more often, Fastener Calc or iAlignTest?
Fastener Calc ships an update every 4 months, and iAlignTest every 32 months. Most recently, Fastener Calc was updated on October 20, 2026 and iAlignTest on October 14, 2026.

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