A forklift scale is an onboard weighing system that measures load weight directly through the forks, eliminating the need to stop at a floor scale. It allows operators to capture weight data "on-the-fly" during normal lifting operations, dramatically improving throughput in shipping, receiving, and inventory management .
How Forklift Scales Work
Forklift scales mount between the forklift carriage and the forks. When the operator lifts a pallet, load cells or hydraulic sensors measure the force, convert it to a weight reading, and display it in the cab—all within 1-2 seconds of the lift .
Two main technologies dominate the market:
Load Cell Carriage Scales use precision sensors (load cells) mounted between front and rear steel plates. As the load presses down, the front plate deflects slightly, and load cells measure this force with high accuracy (typically ±0.1% to ±0.5% of capacity). These are the industry standard for legal-for-trade applications . METTLER TOLEDO's patented 3-point suspension design holds calibration for 12 months, even in harsh environments .
Hydraulic Systems measure pressure increases in the forklift's hydraulic lift cylinders. As the load increases, hydraulic pressure rises proportionally, and sensors convert this to a weight reading. Hydraulic systems are less expensive (some as low as $900) but less accurate (typically ±2% of capacity). They are best suited for overload protection rather than commercial weighing .
Key Specifications
Specification Typical Range What It Means
Maximum Capacity 2,000 – 10,000 lbs (up to 5,000 kg) Heaviest load the scale can weigh
Readability 1 – 20 lbs (1 – 5 kg) Smallest weight increment displayed
Accuracy ±0.1% – ±2% of capacity Closeness of measurement to true weight
Stable Weighing Time 1 – 2 seconds Time to display stable weight after lift
Capacity Loss ~15% of forklift capacity Reduction in forklift's lifting ability
ITA Carriage Class Class II, III, IV Must match your forklift's carriage
Legal-for-Trade NTEP certified Required for commercial transactions
Popular Forklift Scale Models
Manufacturer Model Capacity Readability Key Feature
METTLER TOLEDO TLF820-5 5,000 kg 5 kg 3-point suspension, largest viewing window
Rice Lake CLS Class III 8,000 lbs 5 lbs Cable-less option, VIRTUi³ software
Avery Weigh-Tronix FLSC 5,000 lbs Not specified Patented scale carriage design
Fairbanks FHX Series 20,000 lbs ±0.2% accuracy Hydraulic system for reach trucks
The METTLER TOLEDO TLF820 series installs in under 30 minutes, features a virtual terminal (no physical display to block visibility), and can withstand 150% overload without damage . Rice Lake's CLS series offers wireless communication via Bluetooth, Wi-Fi, and a cable-less option with 24-hour battery life .
Forklift Scale vs. Floor Scale
Forklift Scale Floor Scale
Where weight is captured At the lift point — while moving At a fixed weigh station
Workflow interruption None Load must be set down
Typical accuracy 0.1% – 0.5% of capacity 0.02% – 0.1% of capacity
Legal-for-trade option Yes (NTEP-certified models) Yes
Best for High-volume throughput, large facilities Precision batching, check-weighing
Installation Certified carriage installation Fixed floor mount
Forklift scales shine in high-volume environments where stopping at a floor scale would cripple productivity. For outbound shipments and receiving, a forklift scale can save hours per shift. Many facilities run both—floor scales for precision batching and forklift scales for throughput-oriented weighing .
Installation and Compatibility
Installation typically takes 30 minutes or less . The process involves removing the forks, hanging the scale on the existing ITA carriage, and reattaching the forks to the front plate . No forklift modification is required.
Carriage Class Compatibility is critical. Forklift scales are designed for specific ITA carriage classes:
Class II: 16" carriage height, up to 5,500 lbs capacity
Class III: 20" carriage height, 5,500 to 11,000 lbs capacity
Class IV: 25" carriage height, 11,000 to 17,600 lbs capacity
Your forklift scale must match your carriage class exactly—this is a safety and compatibility requirement, not a preference .
Safety and Operational Considerations
Capacity Loss: Adding a forklift scale reduces the forklift's net lifting capacity by approximately 15% due to the weight of the scale itself and the extended load center . For example, a 5,000 lb capacity forklift may only lift 4,250 lbs with a scale installed. OSHA requires the end user to de-rate the lift capacity when installing any attachment .
Visibility: Quality forklift scales feature a hollow center design that creates a viewing window, allowing operators to see through the scale to the fork tips when the mast is raised .
Data Integration: Modern forklift scales transmit weight data wirelessly to warehouse management systems (WMS), ERP systems, or printers via Bluetooth, Wi-Fi, or USB . Data can be merged with pallet IDs for automated invoicing and inventory tracking .
Legal-for-Trade Certification
If you need weights for billing, shipping manifests, or other commercial transactions, you require an NTEP (National Type Evaluation Program) certified scale (or local equivalent outside the US). Non-certified scales are suitable for internal inventory tracking and overload protection only .
METTLER TOLEDO's forklift scales are approved according to national and international regulations for legal-for-trade applications . Rice Lake offers both NTEP and non-NTEP versions of their CLS series .
The Bottom Line
Forklift scales transform standard forklifts into mobile weighing stations, eliminating costly detours to floor scales. The carriage-based load cell design dominates the market for durability and accuracy, with legal-for-trade options available for commercial applications . Installation takes under 30 minutes, but you must match your forklift's carriage class exactly. Expect a 15% reduction in lifting capacity and plan for wireless data integration to maximize efficiency. For high-volume shipping and receiving, the productivity gains typically pay for the investment within months .