TowWithin checks your vehicle's published towing specs against your trailer's weight — across four metrics — and tells you whether your setup is within those limits, close to one of them, or over. Know before you tow.
The problemMost people tow by feel, not by spec
Towing over capacity is one of the most common causes of trailer sway, brake failure, and loss of control. Vehicle tow ratings are buried in owner's manuals and vary by trim, engine, and axle package. Most drivers tow by feel, not by spec. TowWithin pulls the numbers together and gives you a clear answer.
What it does
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Vehicle Database
Search by year, make, model, and trim for factory tow ratings — GVWR, GCWR, payload, and tow capacity — sourced from manufacturer specs.
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4-Point Safety Check
Checks trailer GTW against tow capacity, tongue weight against payload, total combined weight against GCWR, and trailer weight against GVWR. Four checks, one clear result — and it flags the case where you are technically within the published figures but have almost no margin left.
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Tongue Weight Calculator
Enter your trailer's gross weight and TowWithin estimates tongue weight at 12% — or override it with a scale reading.
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Save Vehicle + Trailer Profiles
Save your truck and trailer combination for instant recheck when load changes.
How it works
- 1
Select your vehicle
Search by year, make, and model. Pick your trim to get the exact factory ratings.
- 2
Enter trailer weight
Gross trailer weight (GTW) and tongue weight — or use the estimated 12% default.
- 3
See where you stand
Four-point result: tow capacity, payload, GCWR, GVWR — with exact margins, and which limit binds first.
Who it's for
- Truck and SUV owners buying or renting a new trailer
- RV owners verifying their tow vehicle can handle upgrades
- Contractors hauling equipment trailers on job sites
- Anyone who wants to know before they hitch, not after something goes wrong
Pricing
Unlimited checks. Full vehicle database (2000–2024). Save unlimited profiles. No subscription. All sales final; refund requests subject to Google Play policy.
Available on Google PlayQuestions
Does the app require an internet connection?
Not for the math. Every calculation runs on your device, and a bundled vehicle dataset works offline. Searching our full vehicle database, scanning a VIN, redeeming a promo code, and serving ads on the free tier do use a connection. You can always enter your vehicle's specs by hand and work entirely offline.
What data does the app collect?
Your saved vehicle and trailer setups, your history, and your preferences stay on your device and are never sent to us. The free tier shows ads through Google AdMob, which uses your device's advertising ID; purchases are validated through RevenueCat under an anonymous ID; and vehicle searches reach our server. We never ask for your name, email, or an account. The full detail is in the TowWithin Privacy Policy.
How often is the data updated?
Vehicle specs cover model years 2000–2024. App updates deliver new datasets without requiring a new purchase.
Can I use it for commercial purposes?
Yes. It's commonly used by contractors and professional drivers. The one-time price covers all use cases.
- One-time purchase — no subscription
- No account required
- Your saved setups stay on your device
- Built for Android, iOS coming
QuassLabs Foundry builds utility apps for people who work in the field — truckers, boaters, tow-vehicle owners, and outdoor professionals. No subscriptions, no accounts required. Buy once, own it.
Foundry apps do their work on your device: what you save stays on your phone. Contact: taylor@quass.org
TowWithin compares the figures you enter against published manufacturer limits, for informational purposes only. It is not an inspection, a certification, or a substitute for your owner's manual. Your vehicle's real capability may be lower than its published rating because of wear, modifications, actual loaded weight, load distribution, and conditions. Always consult your owner's manual and the door-jamb and hitch placards, weigh your loaded combination at a certified scale, and avoid towing at or near your limit. QuassLabs is not liable for accidents, damages, or equipment failure resulting from use of this app. See the TowWithin Terms of Use and Privacy Policy.