Towing Capacity, Tongue Weight & Setup
How to Measure Tongue Weight
Twenty minutes and no special tools for the free method. It is the highest-value thing you can do before a trip.
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Short answer
At a public scale: weigh the tow vehicle with the trailer hitched and the trailer's wheels off the platform, then weigh it with the trailer unhitched. The difference is your tongue weight. It should be 10 to 15 percent of the loaded trailer's weight.
Method one: the public scale (free, most accurate)
At a weighbridge
Load the trailer exactly as you tow it
Water, propane, gear, bikes - everything. A measurement of a half-loaded trailer tells you nothing useful.
Weigh the complete rig
Everything on the platform. This gives you combined weight.
Reposition so only the tow vehicle is on the platform
Trailer still hitched, trailer wheels off the scale. Note this figure.
Chock the trailer and unhitch
Chocks first, always. Pull the tow vehicle back onto the platform alone and note the figure.
Subtract
Hitched vehicle weight minus unhitched vehicle weight equals tongue weight. Combined weight minus unhitched vehicle weight equals loaded trailer weight.
Divide
Tongue weight divided by loaded trailer weight. You want 0.10 to 0.15.
Method two: a dedicated tongue weight scale
Level ground, trailer loaded, coupler lowered onto the scale at normal towing height. Read the number directly. The requirements that matter are level ground and the correct coupler height - a trailer sitting nose-high or nose-low on the scale gives a reading for a position you do not tow in.
Method three: a hitch with a built-in gauge
An adjustable drop hitch with a hydraulic gauge in the shank reads as you lower the trailer onto the ball. The advantage is not accuracy, it is frequency: you get the number every single time you hitch up, including the trips where you would never have gone out of your way to measure. It is slope-sensitive, so a reading taken on a cambered driveway is approximate.
Quick picks
Tap any row to jump to the full write-up. How these are chosen - and what we do and do not claim to know - is published in full on our research methodology page.
| # | Product | Best for | Our read | Price |
|---|---|---|---|---|
| 1 |  Sherline Trailer Tongue Weight Scale Best dedicated tool | Measuring tongue weight at home | Direct reading under the coupler | Check price on Amazon #ad Affiliate link - we publish no price; Amazon shows the current one |
| 2 |  Weigh Safe Adjustable Drop Hitch with Built-in Tongue Weight Scale Measures every time | Owners who will never visit a scale | Gauge built into the shank | Check price on Amazon #ad Affiliate link - we publish no price; Amazon shows the current one |
| 3 |  Camco Trailer Wheel Chocks Required for the free method | Every trailer, without exception | Chock before you unhitch | Check price on Amazon #ad Affiliate link - we publish no price; Amazon shows the current one |
1. Best dedicated tool
Sherline Trailer Tongue Weight Scale
Sherline · Best for measuring tongue weight at home
A dedicated scale you sit under the coupler to read tongue weight directly, with no arithmetic and no trip to a weighbridge. It is the one tool on this site that turns the single most important towing number from a guess into a measurement.
We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.
What works
- Direct reading, with no bathroom-scale-and-lever arithmetic
- Repeatable, so you can see what moving the load actually does
- Mechanical gauge with no batteries to be flat when you need it
What does not
- Must be used on level ground with the coupler at towing height
- Single-purpose tool that spends most of its life in a cupboard
Skip it if
Unnecessary if your hitch already has a built-in gauge, or if you have a public scale nearby and are happy to use it.
#ad Affiliate link - we publish no price; Amazon shows the current one
Raw specifications: Sherline’s own page. We earn nothing on that link.
2. Measures every time
Weigh Safe Adjustable Drop Hitch with Built-in Tongue Weight Scale
Weigh Safe · Best for owners who will never visit a scale
An adjustable drop hitch with a hydraulic gauge in the shank, so the tongue weight reads out as you lower the trailer onto the ball. It turns the single most-skipped step in towing into something that happens automatically, which is worth more than the hardware itself.
We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.
What works
- Reads tongue weight every time you hitch, with no extra step
- Adjustable height and reversible for rise as well as drop
- Makes the 10-15 percent rule checkable instead of theoretical
What does not
- The gauge reads at the ball, so it is sensitive to being parked on a slope
- Heavier and considerably more expensive than a plain mount
Skip it if
Not needed if you already weigh at a public scale - the gauge is convenience, and a certified scale is still the more accurate number.
#ad Affiliate link - we publish no price; Amazon shows the current one
Raw specifications: Weigh Safe’s own page. We earn nothing on that link.
3. Required for the free method
Camco Trailer Wheel Chocks
Camco · Best for every trailer, without exception
Chocks go in before you unhitch, every time. They are not an upgrade and they are not interesting; they are the thing standing between a parked trailer and a slow roll down a campground slope.
We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.
What works
- Cheap insurance against the most preventable trailer accident there is
- Works on any trailer regardless of brakes or jack type
- Takes seconds and needs no setup
What does not
- Plastic chocks degrade in sun over several seasons
- Easy to leave behind at a site
Skip it if
There is no situation where you should skip chocks - if these do not suit your tire size, buy different ones rather than none.
#ad Affiliate link - we publish no price; Amazon shows the current one
What to do with the answer
| Result | Meaning | Action |
|---|---|---|
| Below 10 percent | Sway risk | Move cargo forward of the trailer's axles |
| 10 to 15 percent | In range | Check it fits inside your remaining payload |
| Above 15 percent | Overloading the tow vehicle's rear | Move some weight rearward, or reduce load |
| In range but over payload | Vehicle limit, not trailer balance | Reduce total load or change tow vehicle |
Key takeaways
- The public scale method is free, accurate and needs no tools.
- Chock the trailer before unhitching for any method.
- Measure the trailer loaded the way you actually tow it.
- A result in range still has to fit inside your vehicle's payload.
How we sourced this
Every figure on this page came from one of the following, each fetched while the page was written. Where a manufacturer or regulator does not publish a number, we say so rather than estimate it.
Common questions
- Where can I find a public scale?
- Truck stops, grain elevators, recycling and scrap yards, and some landscaping suppliers commonly have certified scales available for a small fee or free.
- Can I measure at home with bathroom scales?
- The plank-and-lever method exists and we do not recommend it. The arithmetic multiplies small errors and the setup is unstable under several hundred pounds.
- Does it matter if the trailer is not level when I measure?
- Yes. Tilt shifts load between the coupler and the trailer's axles, which is exactly the quantity you are measuring. Level ground and normal towing height both matter.
More in Towing Capacity, Tongue Weight & Setup
The number in the brochure is not the number that limits you. The one that does is on a sticker inside your driver's door.
Read next
Guide
What Is Tongue Weight?
A plain explanation of tongue weight, the 10-15 percent band, and what goes wrong above and below it.
Best tongue weight tool
Best Tongue Weight Scales
Dedicated scales, scale-equipped hitches and the public weighbridge method compared on accuracy and how often you will actually use them.
Guide
Why Trailers Sway
The physics in plain terms, the three causes ranked by how often they are to blame, and how to tell which one you have.
Head to head
Payload vs Towing Capacity
Why the tow rating rarely binds first, how to calculate your real limit from the labels on your vehicle, and what counts against payload.
Found something out of date, or a figure you can source better than we did? Corrections get read first. How we research explains how these pages are put together, and contact is one click away.