This calculator needs JavaScript. Without it, use the formula and examples below the tool.

1. Scale ticket

Type the weights from your CAT scale ticket, in lb. Everything is calculated on your device.

Add it to check the steer axle and gross weight.

The Drive line on the ticket.

The Trailer line on the same ticket.

Axle-group limit

2. Your trailer

Hole spacing

Center of one hole to the center of the next on the slider rail.

From the kingpin to the rear axle of the tandem group, at the hole it sits in now.

How do I measure it?

Measure along the trailer from the center of the kingpin to the center of the rear axle group, with the tandems in their current hole. Use a long tape and measure twice.

Diagram of the kingpin-to-rear-axle distance measured along a semi trailer
More options

Leave blank to bring an axle group that is over its limit down to the limit. Enter a weight to slide to it in either direction.

Default 12,000. Your real limit is set by your tire and axle ratings.

3. Result

Fill in your ticket and trailer to see the result here.

Was this close to your re-weigh?

4. Re-weigh and calibrate

Slide, weigh again, and enter the second ticket. We work out how much weight one hole really moves on your rig and can use that instead of the formula.

Which way did you slide?

Free tool by AltitudeCraft. The full version has the formula, a weight-per-hole chart and worked examples.

Estimate only. Re-weigh before you drive. Follow your state's rules. Your numbers stay on this device unless you send feedback.