Comparison

Bolt Torque Spec Calc vs Coil Toolkit Pro

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

Head to head
About

Bolt Torque Spec Calc

Features
Read full description

Built for mechanics, millwrights, and equipment installers who need bolt torque on the bench - not a desktop tool. WHAT IT DOES Looks up torque values for standard bolt sizes and grades using the T = K x D x F formula with K = 0.20. SAE grades 2, 5, and 8 across 28 sizes from #6-32 to 1-1/2 inch. Metric classes 4.6, 8.8, 10.9, and 12.9 across 17 sizes from M3 to M36. Dry vs. lubricated multiplier applied to the result. INPUTS - Standard: SAE or Metric - Bolt size (28 SAE or 17 metric sizes available) - Bolt grade or class - Lube condition: Dry or Lubricated RETURNS - Torque in ft-lb - Torque in NĀ·m CALCULATION BASIS - Torque formula: T = 0.20 x D x F - Preload F = 75% of proof strength times tensile stress area - Lubricated multiplier: 0.75 times the dry value WHY THIS APP, NOT THE FREE ONES - Math is shown - formula and assumed K factor visible, not hidden. - 45 size and grade combinations covered in one tap. - Works offline - shop floor, field repair, no Wi-Fi. Always available. - No login. No ads. No telemetry. No subscription. PRICING $1.99. Pay once, own it. Lifetime access on iPhone, iPad, and Mac via Family Sharing. NOT A SUBSTITUTE FOR Manufacturer-specified torque values for safety-critical fasteners. Calibrated wrench certificates. Specific K-factor adjustments for anti-seize, plating, or galvanized threads - this app uses K = 0.20 for both dry and lubricated, with the 0.75x multiplier as the only lube adjustment. Verify against the OEM tightening spec for the specific application.

About

Coil Toolkit Pro

Features
Read full description

Coil Calculator is a powerful and easy-to-use inductance calculator designed for engineers, electronics hobbyists, HAM radio operators, students, and DIY enthusiasts. Quickly calculate the inductance, number of turns, wire length, coil dimensions, and other essential parameters for a wide variety of coil types. Whether you're designing RF circuits, audio crossovers, wireless power systems, or custom inductors, Coil Calculator helps you achieve accurate results in seconds. Key Features: • Single-Layer Air Core Coil Calculator • Multi-Layer Air Core Coil Calculator • Ferrite Toroid Inductor Calculator • Ferrite Choke Calculator • Flat Spiral Coil Calculator • PCB Coil Calculator • Inductance and Turns Calculation • Wire Length and Coil Dimension Estimation • Fast, Accurate, and Easy-to-Use Interface • Ideal for RF, Audio, Electronics, and DIY Projects • Works Offline – No Internet Required Perfect For: • HAM Radio Operators • Electronics Engineers • Electrical Engineering Students • Audio Enthusiasts • Makers and DIY Builders • Circuit Designers and Hobbyists Whether you need to calculate the required turns for a target inductance or determine the inductance of an existing coil, Coil Calculator provides reliable results to simplify your design process. Download Coil Calculator today and build better inductors with confidence.

Screenshots

Bolt Torque Spec Calc3 screens
Coil Toolkit Pro4 screens

Verdict

The call

The clearest difference is price: Coil Toolkit Pro at Free against Bolt Torque Spec Calc's $4.99. Coil Toolkit Pro also leads on iOS requirement (13.0 vs 17.0). On ads, in-app purchases and device support there is nothing between them.

Scored on Price Ā· Rating Ā· Positive reviews Ā· Number of ratings Ā· Update frequency Ā· Ads Ā· In-app purchases Ā· Monetization Ā· Best chart rank Ā· Devices Ā· Requires iOS

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

Coil Toolkit Pro is free to download; Bolt Torque Spec Calc costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Scorecard2 real differences Ā· 4 level
Bolt Torque Spec Calc versus Coil Toolkit Pro: the parameters behind the verdict, then further details
ParameterBolt Torque Spec CalcCoil Toolkit Pro
Price$4.99Free — better
Update frequencyEvery 3 weeks—
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPadiPhone, iPod
Requires iOS17.013.0 — better
Further details — not scored
Size1 MB29 MB
Age rating4+4+
DeveloperShanghai Sheyuan Network Technology Co., Ltd.Mamta Kevadiya

In-app purchases

None

Bolt Torque Spec Calc

No in-app purchases

None

Coil Toolkit Pro

No in-app purchases

Questions

Is Bolt Torque Spec Calc free?
Bolt Torque Spec Calc costs $4.99, with no in-app purchases.
Is Coil Toolkit Pro free?
Coil Toolkit Pro is free to download, with no in-app purchases.
Do Bolt Torque Spec Calc or Coil Toolkit Pro have ads?
Neither Bolt Torque Spec Calc nor Coil Toolkit Pro shows ads.

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