Browser-only tool
Axle Load Tire Capacity Checker
This is a rough screen — not a load approval. The checker divides axle load equally among tires, which is a simplification. Side-to-side load distribution, single versus dual ratings, GAWR, wheel ratings, and the required inflation pressure from the manufacturer's table all require separate verification. The tool runs in your browser and does not send data anywhere.
When to Use This Tool
Use this as a first-pass check when adding cargo to a trailer, evaluating a tire substitution for a specific axle, or quickly estimating whether a tire size has adequate capacity before pulling up the manufacturer's full load and inflation table. Do not use it as the sole basis for approving a tire for service — always verify with the manufacturer's current table and the vehicle's GAWR.
How to Use
- Determine the axle load. A scale weight is most accurate. If estimating, use the loaded GVW divided by the number of axles as a rough starting point — then verify with an actual scale when possible.
- Enter the axle load in pounds under "Axle load."
- Enter the number of tires on that axle: 2 for a steer or single-tire axle, 4 for a standard drive or trailer tandem position.
- Look up the rated capacity per tire from the tire manufacturer's current load and inflation table. Use the dual tire rating for dual-mounted tires and the single rating for wide-base singles. Enter this figure in pounds.
- Click Check. The result shows load per tire compared to the entered capacity and whether the rough screen passes or flags a potential overload.
Reading the Result
A "rough screen passes" result means the entered figures show load per tire below entered capacity. It does not mean the tire is approved for that load. GAWR, wheel rating, and the inflation pressure required to achieve that rated capacity all still need to be verified separately.
A "warning" result means the per-tire load exceeds the entered rated capacity. Options are to reduce the axle load, verify the tire rating is correct from the manufacturer's table, check whether a higher load-range tire is appropriate for the position, or consult a qualified technician.
The checker divides load equally between tires. In practice, side-to-side loading is rarely perfectly equal, especially on trailers with off-center loads. If the screen shows little margin, the real situation may be tighter than the calculation suggests.
Example Scenario
A loaded steer axle weight is entered alongside the number of steer tires (2) and the rated single-tire capacity from the manufacturer's load and inflation table for the tire currently installed. The checker shows whether the per-tire load falls within the entered capacity, prompting verification of the required inflation pressure from the same table.
Formula and Limits
load per tire = axle load ÷ number of tires on axle; compare against entered rated capacity per tire
- Side-to-side loading between the two tires on an axle is assumed equal, which is a simplification.
- Single and dual tire capacity ratings differ — use the correct rating for how the tire is mounted.
- GAWR, wheel load rating, and required inflation pressure still need separate verification against the manufacturer's table and the vehicle placard.
- Scale weight is more reliable than estimated load. Conservative estimation of axle weight is recommended when scale weight is not available.
This tool is for planning and rough screening only. It does not replace tire manufacturer load/inflation tables, vehicle placards, professional tire inspection, or compliance guidance from the applicable regulation or carrier policy.