Freight class 60
Changing a unit label must convert the measurement, not reinterpret it.
30 to under 35 lb/ft³
The lower boundary of 30 lb/ft³ is included. Exactly 35 lb/ft³ enters class 55.
2025 density scale. Item confirmation required.
Where this class 60 example sits
Toward class 65: 32.5 − 30 = 2.5 lb/ft³ above the cutoff. The lower edge remains included. Toward class 55: 35 − 32.5 = 2.5 lb/ft³ to the next boundary.
The same compact unit in inches and centimeters
A 36 × 24 × 24 in finished handling unit occupies 12 ft³. Its 390 lb gross weight produces 32.5 lb/ft³ and class 60.
The equivalent dimensions are 91.44 × 60.96 × 60.96 cm, with 176.9010243 kg gross weight. Converting these quantities describes the same physical load. Its density in pounds per cubic foot and its class should remain unchanged.
| Scenario | Quantity × L × W × H; weight per unit | Total volume | Density | Class |
|---|---|---|---|---|
| Correct gross weight: 390 lb | 1 × 36 × 24 × 24 in at 390 lb each | 12 ft³ | 32.5 lb/ft³ | 60 |
| Kilogram number entered as pounds | 1 × 36 × 24 × 24 in at 176.901 lb each | 12 ft³ | 14.742 lb/ft³ | 85 |
| Same envelope at 420 lb | 1 × 36 × 24 × 24 in at 420 lb each | 12 ft³ | 35 lb/ft³ | 55 |
Hypothetical measurements. Calculator Methodology.
Compare the measured scenarios
Unrounded density; rounded display labels.
A unit error is much larger than a rounding error
Typing 176.901 as pounds instead of kilograms cuts the entered weight by more than half. The estimated density becomes about 14.742 lb/ft³, which is class 85. This is a data-entry error, not an effect of changing measurement systems.
At the original 12 ft³ volume, 360 lb is the lower boundary of class 60 and 420 lb is the beginning of class 55. Check the unit shown beside the weight before interpreting either threshold.
The class 55 target stays the same in either unit system
For 390 lb at the 36 × 24 in footprint, the threshold height is 156/7 inches, approximately 22.286. Use the exact fraction for this arithmetic check; rounding the height upward moves below 35 lb/ft³.
| Boundary density | Target volume | Total height | Class at boundary |
|---|---|---|---|
| 35 lb/ft³ | 11.143 ft³ | 22.286 in (156/7 exact) | 55 |
Arithmetic target; confirm safe packaging.
Questions before you ship
What density unit does the class 60 band use?
The 30 to under 35 interval is in pounds per cubic foot, not kilograms per cubic meter. The calculator accepts centimeters and kilograms as inputs, converts them, and reports density in lb/ft³ for this chart.
Related density bands
Sources
Reviewed 2026-10-25: NMFTA scale; effective July 19, 2025; packaging margin (2026).
Conversions: NIST Handbook 133, 2026 Appendix E.
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