Not on the current density scale
Class 77.5 exists as a class number, but no band of the current NMFC density scale produces it. If a calculator hands you 77.5 from a density, it is reading an obsolete chart.
An older, finer-grained density guideline — still hard-coded into a number of free calculators — mapped 13.5 - 15 pcf to class 77.5. The current NMFC density scale does not. Density in that range falls in the 12 - 15 pcf band and rates class 85.
The number has not been abolished. Specific NMFC items can still carry class 77.5, and it can legitimately appear on a rate sheet for that reason. What it cannot be is the output of a density calculation.
It is running the old guideline. That is not a cosmetic difference: the two charts map the same shipment to different classes and therefore different rates. A BOL tendered at class 77.5 on density grounds invites a reclass at the terminal, billed after the fact at the corrected class plus a correction fee.
We tested this. As of August 2026, several widely-used free freight class calculators still return 77.5 for 13.5 - 15 pcf freight — see the calculator audit for the reproducible test results.
| Obsolete guideline | Current NMFC scale | |
|---|---|---|
| Density | 13.5 - 15 pcf | 12 - 15 pcf |
| Class | 77.5 | 85 |
Thirteen sub-provisions, running from class 50 for freight at 50 pcf and above down to class 400 for freight under 1 pcf. NMFC Docket 2025-1, effective 19 July 2025, expanded the previous 11-sub scale to 13: it narrowed the top band to 30–35 pcf at class 60, and added class 55 for 35–50 pcf and class 50 for 50 pcf and over. The full table is on the freight class chart.