Lifting Calculator App

The Close the Hooks app is designed as a practical tool for construction sites, especially when lifting operations require precise planning and mathematical justification. The app helps users calculate:

• Inclination angles and exact sling tensions, calculated according to different lifting angles and pick points.
• Stress level on any individual sling, whether using chains, webbing slings, or other lifting gear.
• Symmetrical and asymmetrical lifts – even in complex situations caused by height differences between lifting points or asymmetrical hook positions.
• Balancing and center of gravity– such as using a turning pulley or lifting slanted elements safely.
• Required sling shortening for asymmetrical elements.

The purpose of the application is not just to save time, but to raise the level of safety on construction sites. It brings forward the same calculation methods presented in the Close the Hooks book and turns them into practical tools for everyday use.

The application is web-based and requires no installation. It is designed especially for lifting operation planners, tower crane operators, riggers, and anyone who wants to move lifting work beyond guesswork and routine – toward measurable and justifiable safety.