When people ask me what the five specs of a crane are, I always say the same thing:
“Make sure you always check the rated lifting capacity, the max working radius, the max lifting height, the tail-swing radius, and the boom length.”
These five specs are what tell you if a crane can do the on-site lifting job you need done safely. If you’re comparing different crane models, those are the specs that are worth comparing.
Now, let’s break it down. Just the simple, real-world stuff you need on the job. No unnecessary explanations or jargon.
What Are the 5 Specifications of a Crane And Why They Matter？
Rated Lifting Capacity — “Can it lift the load?”
This is the first spec that we all look at, but it is also the most misunderstood.
Max lifting capacity is how much weight the crane can lift, but only under certain conditions.
If the load is far away from the crane, or if the boom is extended too far, that “25-ton crane” may only be able to lift 4–5 tons.
This number is basically your go or no-go safety line. (read more： What is a Load Moment Limiter for Tower Crane and How Does It Work?）
Maximum Working Radius — “How far can it reach while lifting?”
The working radius is how far the center of the crane is from the hook.
The larger the radius, the weaker the crane.
This is where the majority of mistakes happen.
If your load is sitting behind a fence, pipe rack, or retaining wall, the radius expands—sometimes without people noticing—and the crane suddenly becomes under-rated for the lift.
Max Lifting Height — “How high do you need the hook to go?”
We’ve seen a few people get this wrong.
The lift height will always be different from the length of the crane boom.
Factors such as boom angle, extensions, and the lift block will all impact your height.
When you’re on a high wall, lifting onto a rooftop, or reaching over structures, this spec is more important than anything else.
Tail-Swing Radius — “Can the crane physically fit in the job site?”
Let’s imagine you’ve found a perfect crane that has the perfect job and the perfect lifting capability. But wait, does that crane even have a proper safe radius malfunction?
Tail-swing radius informs people how much space the back end of the crane needs during rotation.
In tight job sites — factories, power plants, construction sites on the road, and space between two buildings — this spec can literally decide if the crane can even get on the job site.
Boom Length — “What’s the real working range?”
Having tall structures and long horizontal reaches, boom length becomes a major deciding factor.
- Boom length defines your height and radius potential.
- Longer boom length also reduces lifting capacity.
- Always think of it as the crane’s work envelope.
As your boom length increases, so does the height of your lift and the reach of your lift.
How These 5 Specifications Interact
No spec among a crane’s specs works in isolation. They affect each other. That’s where inexperienced planners fall into a trap.
- Long boom → More reach but less lift capacity
- Greater radius → Safe lift weight drastically lowers
- Add a jib → More height, less capacity
- Large tail swing → More space required on job site
- Just because it’s high capacity on paper doesn’t mean it’s high capacity at a long radius.
| Job Site Scenario | Critical Parameter | Potential Risk Point | Why Problems Occur |
| Lifting inside a factory/workshop | Tail-Swing Radius | Insufficient crane slewing space | The counterweight tail collides with pipelines or equipment |
| Lifting materials on roofs / exterior walls | Max Lifting Height + Boom Length | Height available but not “effective height” | Low boom angle results in insufficient vertical reach |
| Long-distance lifting | Working Radius | Lifting beyond the rated radius capacity | Actual capacity at the working radius is far below the required load |
| Heavy equipment lifting | Rated Capacity | Only looking at “maximum lifting capacity” | The rated load drops sharply as the radius increases |
| Compact jobsites / city streets | Tail-Swing Radius | The rated load drops sharply as radius increases | Requires a small-tail or zero-tail-swing crane |
5 Specifications of 10 Commonly Used Cranes
| Crane Model | Rated Lifting Capacity | Max Working Radius | Max Lifting Height | Tail-Swing Radius | Boom Length |
| Tadano ATF 600G-8 | 600 t | ~104 m | ~147 m | – | 15.2–56 m |
| Tadano ATF 400G-6 | 400 t | 86 m | 125 m | – | 15–60 m |
| Tadano ATF 220G-5 | 220 t | 84 m | 107.5 m | – | 13.2–68 m |
| Grove GMK5130-1 | 130 t | ~56 m | ~61 m | 4.36 m | 6-section main boom |
| Liebherr LTM1095-5.1 | 95 t | 54 m | 58 m | 3.78 m | 6-section boom |
| Liebherr LTM1130-5.1 | 130 t | 56 m | 60 m | 4.20 m | 6-section boom |
| Liebherr LTM1100-5.2 | 100 t | 66 m | 84 m | 3.84 m | 11.5–52 m |
| Demag AC 100-4 | 109 t | 44 m | 77 m | – | 12–59 m |
| Grove GMK4090 | 90 t | – | – | 3.5 m | 51 m + jib |
| Liebherr LTM1060-3.1 | 60 t | 48 m | 63 m | – | 48 m boom |
Summary
- Rated Lifting Capacity — tells you if it can actually lift the load
- Working Radius — tells you how far it can reach
- Lifting Height — tells you how high above the ground it can place the load
- Tail-swing Radius — tells you if it will physically fit on your job site
- Boom Length — tells you the overall working envelope and coverage
These five specs give you a realistic view and understanding of a crane and what it can do. Then you are able to benchmark the claims made in a manual.
These numbers have a strong interconnection and relation to each other. Once you can sort that out, it will be easier to compare crane models. Then you will be able to pick the most efficient and safe machine that is suitable for your line of work.
