Key points
- Payload is everything mounted on the flange: tool, part, adaptors and anything else the arm carries.
- Universal Robots publishes a payload-versus-centre-of-gravity chart for UR5e: the further the load sits from the flange, the less mass is allowed.
- ABB, Universal Robots and FANUC all publish payloads that change with orientation or operating mode, so read the conditions behind the headline figure.
This explainer uses Universal Robots’ and ABB’s published payload information as worked examples. It is general engineering guidance, not a sizing calculation for a specific application.
What the rated figure includes
A robot’s maximum payload is the largest mass the manufacturer allows at the tool flange. That mass includes the end effector itself, not only the part being handled. A 5 kg arm carrying a 1.5 kg gripper has 3.5 kg left for the part before any other limit is considered.
Universal Robots publishes 5 kg for UR5e and ABB publishes 5 kg for GoFa 5. Those figures are the starting point for sizing, not the answer.
Centre of gravity changes the limit
The UR5e PDF datasheet includes a chart of permitted payload against the distance of the load’s centre of gravity from the flange. A long or offset tool puts more moment on the wrist joints than a compact tool of the same mass, so the permitted mass falls as the offset grows.
Whenever the centre of gravity sits away from the flange, read the manufacturer’s chart for your tool rather than the headline figure.
Orientation and configuration
Manufacturers increasingly publish more than one payload figure for the same arm. ABB publishes higher payloads for two GoFa variants in a wrist-down configuration. Universal Robots lists UR20 at 20 kg, or 25 kg with boundary conditions set out in its manual. FANUC's CRX-30iA datasheet describes selectable payload modes that trade reach for load, including a 40 kg mode that keeps the flange facing downwards.
When a datasheet gives several payloads, the headline number is the one that applies under the fewest restrictions. Read the conditions before sizing a tool against the larger figure.
| Robot | Published payload | Condition |
|---|---|---|
| ABB GoFa 10 | 12 kg | Wrist-down configuration |
| ABB GoFa 12 | 14 kg | Wrist-down configuration |
| Universal Robots UR20 | 20 kg; 25 kg | 25 kg with boundary conditions in the manual |
| FANUC CRX-30iA | 30 kg at 1,756 mm reach | Default rating |
| FANUC CRX-30iA | 25 kg at 1,889 mm reach | 25 kg payload mode |
| FANUC CRX-30iA | 40 kg at 1,700 mm reach | 40 kg mode; wrist flange facing downwards |
Beyond mass
Speed and acceleration add dynamic load, and collaborative operation may need lower speeds, set by the risk assessment. Cable and hose packages, tool changers and adaptor plates add mass that is easy to forget. The controller also needs the correct payload mass and centre of gravity so that it can model the arm’s dynamics.
A practical sizing check lists the mass and centre of gravity of everything on the flange, the orientations the task needs, the required speed and the margin you want to keep below the manufacturer’s chart.
Primary sources
- UR5e e-Series datasheet (PDF)Universal Robots · accessed 8 October 2026
- UR5e technical specification (online datasheet)Universal Robots · accessed 8 October 2026
- GoFa collaborative robotsABB Robotics · accessed 8 October 2026
- UR20 technical specification (online datasheet)Universal Robots · accessed 9 October 2026
- CRX-30iA datasheetFANUC Europe · accessed 9 October 2026