# RigMaster: Rigging Calculator — Sling Tension & Load Weight

> Sling Tension & Load Weight (iPhone/iPad app by Grima Hdez.)

- Source: https://appshunter.io/ios/app/rigmaster-rigging-calculator/id6789944360 (this page in markdown: same URL + `.md`)
- Developer: [Grima Hdez](https://appshunter.io/developer/1741481582)
- Category: Utilities, Productivity
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 17.0 · 4 MB
- Languages: Arabic, Dutch, English, French, German, Italian, Japanese, Korean, Portuguese, Russian and 4 more
- Released: 2026-07-19
- Data updated: 2026-09-15
- User reviews in markdown: https://appshunter.io/ios/app/rigmaster-rigging-calculator/id6789944360/reviews.md

## What is RigMaster?

RigMaster is the rigging calculator built for working riggers, crane operators, and signal persons.

LIFT PLAN PDF (PRO)
• Turn any calculation into a one-page lift plan: diagram, inputs, results
• Room for notes and three signature lines — prepared by, signature, date
• Share it straight to the supervisor from the toolbar

IPAD & UNITS
• Universal app — two-column layout on iPad, any orientation
• Metric or imperial — kg and metres or lb and feet, switch any time
• Live sling diagram with the angle and tension on every leg

FREE CALCULATORS
• Sling Tension — 2-leg picks by angle, or by sling length & height (the way you actually measure)
• Hitch Capacity — vertical, choker, and basket capacity from YOUR sling's tag rating
• Angle Reference — the tension multiplier table, always in your pocket

PRO CALCULATORS
• 3 & 4-leg bridles with rigid/flexible load sharing
• Unequal Legs / CoG Offset — tension per leg when the center of gravity isn't centered
• Load Weight Estimator — steel, concrete, aluminum and more, by shape and dimensions
• Ad-free

Built on first-principles trigonometry with warnings at 45° and hard alerts below 30°, following standard rigging practice (ASME B30.9 guidance).

RigMaster is an estimation aid for qualified riggers. Always follow the sling tag, the load chart, and your site's rigging plan.

Terms of Use (EULA): https://ghapps1.wordpress.com/terms-condition/
Privacy Policy: https://ghapps1.wordpress.com/privacy-policy/

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Pro Weekly | $4.99 | per 7 days |
| Pro Yearly | $29.99 | per year |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| RigMaster Pro | $39.99 | one-time |



## Version history (last 5 releases)

### 1.4.0 — 2026-09-07

• The GDPR consent form was not linked into the app at all, so ads could be served in Europe without asking first
• More tests behind the sling and load calculations
• A free trial is only offered to people who can still get one

### 1.3.0 — 2026-08-20

NEW — Lift Plan PDF (Pro)

Turn any calculation into a one-page sheet: the diagram, the numbers it was calculated from, room for notes and three signature lines. Hand that to the supervisor instead of a screenshot.

If RigMaster is doing its job, a rating takes ten seconds and helps other riggers find it.

### 1.2.1 — 2026-08-19

Internal fixes and maintenance.

If RigMaster is doing its job, a rating takes ten seconds and helps other riggers find it.

### 1.2.0 — 2026-08-04

Small internal improvements.

If the app is doing its job, a rating takes ten seconds and helps other people find it.

### 1.1.0 — 2026-07-30

iPad support: every calculator now runs in a two-column layout, in any orientation.
Metric units: work in kg and metres — or stay in lb and feet. Switch any time in Settings.
New sling diagram: see the pick, the angles and the tension on every leg while you type.
Angle reference chart: watch the multiplier climb as the angle drops below 45°.
Bigger, clearer results, plus light/dark themes and text-size options for sunlight and gloves.
RigMaster is now translated into 13 languages.

## More apps by Grima Hdez

- [Decibel Sound Meter: dB SPL](https://appshunter.io/ios/app/decibel-sound-meter-db-spl/id1501310833)
- [Text Reader Narrator: TTS](https://appshunter.io/ios/app/text-reader-narrator-tts/id1501312978)
- [Random: Number, Bingo, Dice](https://appshunter.io/ios/app/random-number-bingo-dice/id1501313323)
- [Drawing And Painting](https://appshunter.io/ios/app/drawing-and-painting/id1501400328)
- [Voice Recorder & To do list](https://appshunter.io/ios/app/voice-recorder-and-to-do-list/id1516155953)
- [Fit as - Register Your Steps](https://appshunter.io/ios/app/fit-as-register-your-steps/id1521810948)

All apps by Grima Hdez: https://appshunter.io/developer/1741481582

## Related topics

[rigging chart](https://appshunter.io/ios/topics/rigging-chart) · [rigging](https://appshunter.io/ios/topics/rigging) · [rigging calculator](https://appshunter.io/ios/topics/rigging-calculator) · [rigging lab](https://appshunter.io/ios/topics/rigging-lab) · [rigging load calculator tool](https://appshunter.io/ios/topics/rigging-load-calculator-tool) · [leo rigging calculator](https://appshunter.io/ios/topics/leo-rigging-calculator) · [rigging app](https://appshunter.io/ios/topics/rigging-app)

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*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 2026-09-15.*