What this tool answers
You need a first-pass trailer tongue jack capacity before buying a weld-on pipe-mount swivel jack. The calculator estimates minimum rating from tongue_lb × 1.25, then names the smallest class on this site’s ladder (5000, 8000, or 12000 lb) that clears the estimate. It is not an installation procedure, tongue-structure study, or substitute for manufacturer instructions.
The 1.25× tongue-weight screening rule
Required capacity ≈ tongue_lb × 1.25. That headroom covers loading variation and shopping margin above a measured tongue weight. Always use tongue weight for the loaded trailer you tow when available, not empty dry tongue weight alone.
Dynamic vs static rating
Listings may quote dynamic (moving / road) or static (parked support) capacity. Confirm which figure the merchant nameplate uses before you buy. Never exceed the nameplate for the duty you intend.
Weld-on mounts and wheel chocks
Weld-on pipe mounts need competent welding to a suitable tongue structure — weak welds or thin tube can fail under load. Before raising or lowering the tongue, chock the trailer wheels on firm, level ground. This site does not certify welds or installations.
Class ladder on this site
Classes are returned as rated pounds: 5000, 8000, and 12000 lb. The tool picks the smallest class whose rated_lb is greater than or equal to required_lb. Only tongue weight in pounds is used.
When the answer is NO_MATCH
If required capacity exceeds 12000 lb (for example tongue 11000 → required 13750), this site returns NO_MATCH for its published class ladder. Typical next steps: a higher-rated industrial jack or professional equipment. Do not force an undersized consumer tongue jack.
Safety notes
Confirm dynamic vs static rating on the listing. Weld-on needs competent welding. Chock wheels. Never exceed nameplate. Work on solid, level ground. Keep people clear of the trailer path. This site does not certify lifts or mounts.
Sources
Trailer and RV practice of sizing tongue jacks above measured tongue weight. Manufacturer safety culture around rated equipment and proper mounting. VEVOR US weld-on trailer jack product pages for rated classes dated in products.json (checked 2026-09-10).