Crane Size Calculator
Enter the load weight, the weight of slings, shackles and hook block, the working radius and the share of the load chart you want to use. The calculator estimates the crane class to shortlist.
- Load at radius
- Rigging included
- Chart limit
Radius is measured from the centre of the crane's slewing ring to the centre of the load.
Crane capacity drops quickly as the load moves out. A crane's headline rating only applies very close in. At 10 m out a crane can lift only about a quarter of its rating, so a 5 t load at 10 m needs a crane of about 35 t or more.
Crane size chart
Load plus 5% rigging, 75% of chart. Search for a radius.
| Radius (m) | 2 t load | 5 t load | 10 t load | 20 t load |
|---|---|---|---|---|
| 5 | 5 | 14 | 27 | 55 |
| 10 | 11 | 27 | 55 | 110 |
| 15 | 16 | 41 | 82 | 165 |
| 20 | 22 | 55 | 110 | 220 |
| 30 | 33 | 82 | 165 | 329 |
Approximate crane class in tonnes. Always confirm with the real load chart.
Radius and crane size
5 t load. Slide the radius.
The boom reaches out to the load at the radius you set.
How to estimate crane size
Load, radius, limit. Step through it.
Weigh the load
Plus rigging.
Ground bearing pressure under the outriggers also limits the lift. Check the ground before booking.
City, all-terrain or crawler
Crane types. Compare them.
Compact for tight sites.
Road legal and powerful.
On tracks, very heavy lifts.
Tower cranes suit long building jobs; mobile cranes suit single lifts and short hires.
Before booking
Lift planning. Tick each item.
Tick each item as you go.
Every lift needs a lift plan by a competent person. Heavy or complex lifts need an appointed person and an engineered plan.
What you get
Crane shortlist. Each tile explains one result.
Tonnes.
Calculated.
With rigging.
Metres.
Used.
Hire companies will confirm the crane from its real chart once you give them load, radius and site details.
Frequently Asked Questions
No question matches that search.
What size crane do I need?
Enough capacity at your radius, not just the headline rating.
What size crane to lift 5 tonnes at 10 m?
Around 35 t or more, depending on the crane's chart.
Why does capacity fall with radius?
The load's tipping moment grows with distance from the crane.
Should I include rigging weight?
Yes, slings, shackles, spreader beams and the hook block all count.
What is a 75% chart limit?
Using no more than three quarters of the chart capacity, a common safety margin.
What is working radius?
Distance from the crane's centre of rotation to the load's centre.
Who checks a lift plan?
A competent or appointed person under lifting regulations.
The right crane for the lift
Add the rigging, measure the radius and allow a safety margin. Use the estimate to shortlist cranes, then confirm with the real load chart.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.