Forklift Guide
Forklift Capacity & Sizing Guide
A “2.5-tonne” forklift can't always lift 2.5 tonnes. This guide explains rated capacity, load centre, and why lifting higher or further reduces what you can safely carry — so you choose a truck that handles your real loads.
The Basics
What “Rated Capacity” Really Means
Rated capacity is the maximum weight a forklift can safely lift — but the headline figure only holds at a specific load centreand lift height. It's a conditional number, not an absolute one. Aexus supplies forklifts across a wide capacity range, commonly from about 1.5 to 10+ tonnes, so matching the truck to your loads is the first sizing decision.
The rating assumes a standard load centre — commonly 500 mm — with the load's centre of gravity that far from the fork face. Change the load, the height, or the attachment, and the safe capacity changes with it.
The Key Idea
Load Centre Explained
Load centre is the horizontal distance from the front of the forks to the centre of gravity of the load. Think of the forklift as a see-saw balanced on its front axle: the load on one side, the truck's weight on the other.
The further the load's centre of gravity sits from the forks, the more leverage it applies — so a long or deep pallet effectively “weighs more” to the truck than a compact one of the same mass. That's why a forklift rated at 500 mm can safely lift less once the load centre moves out to 600 mm or beyond.
Why It Drops
Three Things That Reduce Capacity
“Derating” is the reduction in safe capacity away from the rated conditions. Three factors drive it.
Load centre further out
A long or deep load shifts its centre of gravity away from the forks, adding leverage. The forklift must lift less to stay stable.
Higher lift height
Raising a load higher reduces stability, so rated capacity often falls as the mast extends. High-bay work needs this checked.
Attachments
Clamps, side shifters, and extensions add weight and can push the load centre forward — both reduce the net capacity available for the load.
Where to Look
Reading the Data Plate
Every forklift carries a capacity (data) plate near the operator's seat. It's the authority on what the truck can safely lift — always defer to it, not the model name.
- ✓Model and serial number
- ✓Rated capacity (kg)
- ✓The load centre it applies at (e.g. 500 mm)
- ✓Maximum lift height
- ✓Mast type and, if fitted, attachment details
Fitting an attachment? The plate should be updated to show the derated capacity — never assume the original rating still applies.
Keep Reading
Get the Whole Picture
Common Questions
Capacity & Sizing FAQ
Rated capacity is the maximum weight a forklift can safely lift — but only at a stated load centre and lift height, shown on the data plate. A '2.5-tonne' forklift can lift 2,500 kg only when the load's centre of gravity is at the rated distance (commonly 500 mm) from the fork face. Heavier, longer, or higher loads reduce the safe figure.
Load centre is the horizontal distance from the front face of the forks to the centre of gravity of the load — commonly rated at 500 mm. The further the load's centre of gravity sits from the forks (for example, a long or deep pallet), the more leverage it exerts, and the less the forklift can safely lift.
Because the rating applies at a specific load centre and height. Lifting a load whose centre of gravity is further out than the rated load centre, or lifting to a greater height, reduces the safe capacity — this is called derating. Always check the data plate (and any attachment's effect) for the actual capacity in your situation, never just the headline number.
Size it to your heaviest routine load plus a safety margin, at the load centre and height you actually lift to — not just the average load. Factor in attachments, which add weight and shift the load centre. Tell us your heaviest loads, their dimensions, and your lift height and we'll recommend the right capacity.
On the data plate (capacity or nameplate), usually fixed near the operator's seat. It lists the model, rated capacity, the load centre it applies at, maximum lift height, and mast and attachment details. If an attachment is fitted, the plate should reflect the derated capacity.
Sizing a Forklift to Your Loads?
Send us your heaviest loads, their dimensions, and your lift height — we'll recommend the right capacity with the margin to work safely.