The Offshore Toolkit is a free, growing set of calculators and checkers for the calculations lifting supervisors, riggers, and inspectors actually reach for on the job — SWL/WLL, sling angles, padeye and hook checks, wire rope discard, ATEX/IECEx zones, dropped object consequence, and inspection planning. No signup, no paywall, no catch.
Six calculators so far, each one built to answer a specific question you'd otherwise need a standard, a spreadsheet, or a phone call to a colleague to answer.
Safe Working Load from MBL, sling angle de-rating, and tension per leg on a multi-leg sling.
Calculator 01Basic pass/fail checks for padeyes and hooks/shackles against applied load, with side-load warnings.
Calculator 02Diametric reduction, broken-wire counts (6d and single-strand rules), and a physical damage checklist.
Calculator 03Check equipment category, gas/dust group, and temperature class against a hazardous zone.
Calculator 04DROPS Calculator methodology — classifies likely outcome from mass and fall height, with a banded chart.
Calculator 05Build a year-view wall chart of inspection due dates from your equipment list and print or save it as a PDF.
Calculator 06A lot of the tools this industry relies on for quick checks — SWL tables, sling angle charts, discard criteria — are locked behind a login, an email capture, or a subscription. The Offshore Toolkit isn't. Every calculator is free to use, right now, with nothing to sign up for and nothing collected.
That's a deliberate choice: a rigger checking a sling angle on deck shouldn't have to create an account first.
Every calculator here is built from the actual formulas and criteria in the standards and industry references it's based on — ISO 4309, DROPS methodology, ATEX/IECEx classification — not rough approximations dressed up as fact.
Where a number genuinely depends on equipment-specific certification or engineering sign-off, the tool says so, rather than pretending more precision than it has. These are working checks to support good judgment on site, not a replacement for a certified lifting plan or a competent person's sign-off.
Yes. Every calculator is free to use, with no signup, no account, and no usage limit. It's built to be a genuinely useful reference for the industry, not a lead magnet.
No. These are working checks and references, not a substitute for a certified lifting plan, manufacturer documentation, or sign-off from a competent person or engineer. Always confirm results against the actual rated equipment, tags, and certificates before any lift.
No. Every calculation runs entirely client-side in your browser. Nothing you type into any calculator is sent to a server, logged, or stored anywhere outside your own device.
Lifting supervisors, riggers, deck crews, inspectors, and anyone else working offshore or in industrial lifting who needs a fast, reliable check without digging through a standard or spreadsheet.