Load-at-Pressure Lookup Tool
Find the load a tire can carry at each pressure. Use the calculator below. Results update as you type.
How the Load-at-Pressure Lookup Tool Works
The Load at Pressure Lookup Tool works by reading the tire maker's load-inflation table at your chosen pressure for your size and load category. Load capacity rises with pressure up to the reference pressure.
- Enter the size and load category, for example LT265/70R17, load range E.
- Enter the pressure, for example 60 psi (414 kPa).
- Read the capacity from the applicable maker table.
- Compare with the actual axle load divided by 2.
The Formula
The Load at Pressure Lookup Tool formula is Load = Maker_Table[Size, Load Category, Pressure]. No single equation replaces the maker's table.
Load = Table(Size, Category, Pressure) Pressure (kPa) = psi × 6.89476 Required Load per Tire = Axle Load ÷ 2Worked example: for a 2,400 kg (5,291 lb) rear axle load, each tire must carry at least 1,200 kg (2,646 lb) at the chosen pressure.
Conversion Table
The Load at Pressure Lookup Tool conversion table lists the reference pressure for 8 load categories in psi, kPa and bar, with the pressure where each load table starts. Reference pressure is where a tire reaches its full rated load.
Load range E reaches its full load at 80 psi (550 kPa, 5.5 bar). The note under the table states that pressure above the reference adds no capacity.
| Load Category | Reference psi | Reference kPa | Reference bar | Load Table Starts At |
|---|---|---|---|---|
| Standard Load (SL) | 36 | 250 | 2.5 | 26 psi (180 kPa) |
| Extra Load (XL) | 42 | 290 | 2.9 | 26 psi (180 kPa) |
| LT Load Range C | 50 | 345 | 3.45 | 35 psi (240 kPa) |
| LT Load Range D | 65 | 450 | 4.5 | 35 psi (240 kPa) |
| LT Load Range E | 80 | 550 | 5.5 | 35 psi (240 kPa) |
| LT Load Range F | 95 | 655 | 6.55 | 40 psi (275 kPa) |
| ST Load Range D | 65 | 450 | 4.5 | Single value |
| ST Load Range E | 80 | 550 | 5.5 | Single value |
Load rises with pressure only up to the reference pressure; higher pressure adds no capacity.
What Is the Load-at-Pressure Lookup Tool?
The Load at Pressure Lookup Tool is a tool that finds how much weight a tire carries at a pressure below its maximum. Tire makers publish load-inflation tables from organizations such as the Tire and Rim Association (TRA) and ETRTO.
The tool helps set pressure to match real load. Running full maximum pressure on a lightly loaded truck gives a harsh ride and uneven wear.
Common Uses
The Load at Pressure Lookup Tool has 4 uses: pressure tuning, towing setup, RV setup and plus-size pressure checks.
- Tune pressure: Match pressure to weighed axle loads.
- Set up for towing: Raise rear pressure for tongue weight.
- Set up RVs: Use weighed corner loads.
- Check plus sizes: Adjust pressure to keep capacity.